8351 lines
284 KiB
ReStructuredText
8351 lines
284 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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===================================================================
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The Definitive KVM (Kernel-based Virtual Machine) API Documentation
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===================================================================
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1. General description
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======================
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The kvm API is a set of ioctls that are issued to control various aspects
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of a virtual machine. The ioctls belong to the following classes:
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- System ioctls: These query and set global attributes which affect the
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whole kvm subsystem. In addition a system ioctl is used to create
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virtual machines.
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- VM ioctls: These query and set attributes that affect an entire virtual
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machine, for example memory layout. In addition a VM ioctl is used to
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create virtual cpus (vcpus) and devices.
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VM ioctls must be issued from the same process (address space) that was
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used to create the VM.
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- vcpu ioctls: These query and set attributes that control the operation
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of a single virtual cpu.
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vcpu ioctls should be issued from the same thread that was used to create
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the vcpu, except for asynchronous vcpu ioctl that are marked as such in
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the documentation. Otherwise, the first ioctl after switching threads
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could see a performance impact.
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- device ioctls: These query and set attributes that control the operation
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of a single device.
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device ioctls must be issued from the same process (address space) that
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was used to create the VM.
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2. File descriptors
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===================
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The kvm API is centered around file descriptors. An initial
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open("/dev/kvm") obtains a handle to the kvm subsystem; this handle
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can be used to issue system ioctls. A KVM_CREATE_VM ioctl on this
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handle will create a VM file descriptor which can be used to issue VM
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ioctls. A KVM_CREATE_VCPU or KVM_CREATE_DEVICE ioctl on a VM fd will
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create a virtual cpu or device and return a file descriptor pointing to
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the new resource. Finally, ioctls on a vcpu or device fd can be used
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to control the vcpu or device. For vcpus, this includes the important
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task of actually running guest code.
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In general file descriptors can be migrated among processes by means
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of fork() and the SCM_RIGHTS facility of unix domain socket. These
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kinds of tricks are explicitly not supported by kvm. While they will
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not cause harm to the host, their actual behavior is not guaranteed by
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the API. See "General description" for details on the ioctl usage
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model that is supported by KVM.
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It is important to note that although VM ioctls may only be issued from
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the process that created the VM, a VM's lifecycle is associated with its
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file descriptor, not its creator (process). In other words, the VM and
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its resources, *including the associated address space*, are not freed
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until the last reference to the VM's file descriptor has been released.
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For example, if fork() is issued after ioctl(KVM_CREATE_VM), the VM will
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not be freed until both the parent (original) process and its child have
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put their references to the VM's file descriptor.
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Because a VM's resources are not freed until the last reference to its
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file descriptor is released, creating additional references to a VM
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via fork(), dup(), etc... without careful consideration is strongly
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discouraged and may have unwanted side effects, e.g. memory allocated
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by and on behalf of the VM's process may not be freed/unaccounted when
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the VM is shut down.
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3. Extensions
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=============
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As of Linux 2.6.22, the KVM ABI has been stabilized: no backward
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incompatible change are allowed. However, there is an extension
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facility that allows backward-compatible extensions to the API to be
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queried and used.
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The extension mechanism is not based on the Linux version number.
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Instead, kvm defines extension identifiers and a facility to query
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whether a particular extension identifier is available. If it is, a
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set of ioctls is available for application use.
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4. API description
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==================
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This section describes ioctls that can be used to control kvm guests.
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For each ioctl, the following information is provided along with a
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description:
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Capability:
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which KVM extension provides this ioctl. Can be 'basic',
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which means that is will be provided by any kernel that supports
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API version 12 (see section 4.1), a KVM_CAP_xyz constant, which
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means availability needs to be checked with KVM_CHECK_EXTENSION
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(see section 4.4), or 'none' which means that while not all kernels
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support this ioctl, there's no capability bit to check its
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availability: for kernels that don't support the ioctl,
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the ioctl returns -ENOTTY.
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Architectures:
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which instruction set architectures provide this ioctl.
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x86 includes both i386 and x86_64.
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Type:
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system, vm, or vcpu.
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Parameters:
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what parameters are accepted by the ioctl.
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Returns:
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the return value. General error numbers (EBADF, ENOMEM, EINVAL)
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are not detailed, but errors with specific meanings are.
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4.1 KVM_GET_API_VERSION
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-----------------------
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:Capability: basic
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:Architectures: all
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:Type: system ioctl
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:Parameters: none
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:Returns: the constant KVM_API_VERSION (=12)
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This identifies the API version as the stable kvm API. It is not
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expected that this number will change. However, Linux 2.6.20 and
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2.6.21 report earlier versions; these are not documented and not
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supported. Applications should refuse to run if KVM_GET_API_VERSION
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returns a value other than 12. If this check passes, all ioctls
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described as 'basic' will be available.
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4.2 KVM_CREATE_VM
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-----------------
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:Capability: basic
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:Architectures: all
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:Type: system ioctl
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:Parameters: machine type identifier (KVM_VM_*)
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:Returns: a VM fd that can be used to control the new virtual machine.
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The new VM has no virtual cpus and no memory.
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You probably want to use 0 as machine type.
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In order to create user controlled virtual machines on S390, check
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KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as
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privileged user (CAP_SYS_ADMIN).
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On arm64, the physical address size for a VM (IPA Size limit) is limited
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to 40bits by default. The limit can be configured if the host supports the
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extension KVM_CAP_ARM_VM_IPA_SIZE. When supported, use
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KVM_VM_TYPE_ARM_IPA_SIZE(IPA_Bits) to set the size in the machine type
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identifier, where IPA_Bits is the maximum width of any physical
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address used by the VM. The IPA_Bits is encoded in bits[7-0] of the
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machine type identifier.
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e.g, to configure a guest to use 48bit physical address size::
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vm_fd = ioctl(dev_fd, KVM_CREATE_VM, KVM_VM_TYPE_ARM_IPA_SIZE(48));
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The requested size (IPA_Bits) must be:
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== =========================================================
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0 Implies default size, 40bits (for backward compatibility)
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N Implies N bits, where N is a positive integer such that,
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32 <= N <= Host_IPA_Limit
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== =========================================================
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Host_IPA_Limit is the maximum possible value for IPA_Bits on the host and
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is dependent on the CPU capability and the kernel configuration. The limit can
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be retrieved using KVM_CAP_ARM_VM_IPA_SIZE of the KVM_CHECK_EXTENSION
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ioctl() at run-time.
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Creation of the VM will fail if the requested IPA size (whether it is
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implicit or explicit) is unsupported on the host.
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Please note that configuring the IPA size does not affect the capability
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exposed by the guest CPUs in ID_AA64MMFR0_EL1[PARange]. It only affects
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size of the address translated by the stage2 level (guest physical to
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host physical address translations).
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4.3 KVM_GET_MSR_INDEX_LIST, KVM_GET_MSR_FEATURE_INDEX_LIST
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----------------------------------------------------------
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:Capability: basic, KVM_CAP_GET_MSR_FEATURES for KVM_GET_MSR_FEATURE_INDEX_LIST
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:Architectures: x86
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:Type: system ioctl
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:Parameters: struct kvm_msr_list (in/out)
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:Returns: 0 on success; -1 on error
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Errors:
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====== ============================================================
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EFAULT the msr index list cannot be read from or written to
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E2BIG the msr index list is too big to fit in the array specified by
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the user.
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====== ============================================================
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::
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struct kvm_msr_list {
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__u32 nmsrs; /* number of msrs in entries */
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__u32 indices[0];
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};
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The user fills in the size of the indices array in nmsrs, and in return
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kvm adjusts nmsrs to reflect the actual number of msrs and fills in the
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indices array with their numbers.
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KVM_GET_MSR_INDEX_LIST returns the guest msrs that are supported. The list
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varies by kvm version and host processor, but does not change otherwise.
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Note: if kvm indicates supports MCE (KVM_CAP_MCE), then the MCE bank MSRs are
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not returned in the MSR list, as different vcpus can have a different number
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of banks, as set via the KVM_X86_SETUP_MCE ioctl.
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KVM_GET_MSR_FEATURE_INDEX_LIST returns the list of MSRs that can be passed
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to the KVM_GET_MSRS system ioctl. This lets userspace probe host capabilities
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and processor features that are exposed via MSRs (e.g., VMX capabilities).
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This list also varies by kvm version and host processor, but does not change
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otherwise.
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4.4 KVM_CHECK_EXTENSION
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-----------------------
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:Capability: basic, KVM_CAP_CHECK_EXTENSION_VM for vm ioctl
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:Architectures: all
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:Type: system ioctl, vm ioctl
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:Parameters: extension identifier (KVM_CAP_*)
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:Returns: 0 if unsupported; 1 (or some other positive integer) if supported
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The API allows the application to query about extensions to the core
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kvm API. Userspace passes an extension identifier (an integer) and
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receives an integer that describes the extension availability.
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Generally 0 means no and 1 means yes, but some extensions may report
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additional information in the integer return value.
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Based on their initialization different VMs may have different capabilities.
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It is thus encouraged to use the vm ioctl to query for capabilities (available
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with KVM_CAP_CHECK_EXTENSION_VM on the vm fd)
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4.5 KVM_GET_VCPU_MMAP_SIZE
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--------------------------
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:Capability: basic
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:Architectures: all
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:Type: system ioctl
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:Parameters: none
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:Returns: size of vcpu mmap area, in bytes
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The KVM_RUN ioctl (cf.) communicates with userspace via a shared
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memory region. This ioctl returns the size of that region. See the
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KVM_RUN documentation for details.
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Besides the size of the KVM_RUN communication region, other areas of
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the VCPU file descriptor can be mmap-ed, including:
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- if KVM_CAP_COALESCED_MMIO is available, a page at
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KVM_COALESCED_MMIO_PAGE_OFFSET * PAGE_SIZE; for historical reasons,
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this page is included in the result of KVM_GET_VCPU_MMAP_SIZE.
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KVM_CAP_COALESCED_MMIO is not documented yet.
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- if KVM_CAP_DIRTY_LOG_RING is available, a number of pages at
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KVM_DIRTY_LOG_PAGE_OFFSET * PAGE_SIZE. For more information on
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KVM_CAP_DIRTY_LOG_RING, see section 8.3.
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4.6 KVM_SET_MEMORY_REGION
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-------------------------
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:Capability: basic
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:Architectures: all
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:Type: vm ioctl
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:Parameters: struct kvm_memory_region (in)
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:Returns: 0 on success, -1 on error
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This ioctl is obsolete and has been removed.
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4.7 KVM_CREATE_VCPU
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-------------------
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:Capability: basic
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:Architectures: all
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:Type: vm ioctl
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:Parameters: vcpu id (apic id on x86)
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:Returns: vcpu fd on success, -1 on error
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This API adds a vcpu to a virtual machine. No more than max_vcpus may be added.
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The vcpu id is an integer in the range [0, max_vcpu_id).
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The recommended max_vcpus value can be retrieved using the KVM_CAP_NR_VCPUS of
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the KVM_CHECK_EXTENSION ioctl() at run-time.
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The maximum possible value for max_vcpus can be retrieved using the
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KVM_CAP_MAX_VCPUS of the KVM_CHECK_EXTENSION ioctl() at run-time.
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If the KVM_CAP_NR_VCPUS does not exist, you should assume that max_vcpus is 4
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cpus max.
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If the KVM_CAP_MAX_VCPUS does not exist, you should assume that max_vcpus is
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same as the value returned from KVM_CAP_NR_VCPUS.
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The maximum possible value for max_vcpu_id can be retrieved using the
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KVM_CAP_MAX_VCPU_ID of the KVM_CHECK_EXTENSION ioctl() at run-time.
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If the KVM_CAP_MAX_VCPU_ID does not exist, you should assume that max_vcpu_id
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is the same as the value returned from KVM_CAP_MAX_VCPUS.
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On powerpc using book3s_hv mode, the vcpus are mapped onto virtual
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threads in one or more virtual CPU cores. (This is because the
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hardware requires all the hardware threads in a CPU core to be in the
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same partition.) The KVM_CAP_PPC_SMT capability indicates the number
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of vcpus per virtual core (vcore). The vcore id is obtained by
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dividing the vcpu id by the number of vcpus per vcore. The vcpus in a
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given vcore will always be in the same physical core as each other
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(though that might be a different physical core from time to time).
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Userspace can control the threading (SMT) mode of the guest by its
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allocation of vcpu ids. For example, if userspace wants
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single-threaded guest vcpus, it should make all vcpu ids be a multiple
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of the number of vcpus per vcore.
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For virtual cpus that have been created with S390 user controlled virtual
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machines, the resulting vcpu fd can be memory mapped at page offset
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KVM_S390_SIE_PAGE_OFFSET in order to obtain a memory map of the virtual
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cpu's hardware control block.
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4.8 KVM_GET_DIRTY_LOG (vm ioctl)
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--------------------------------
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:Capability: basic
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:Architectures: all
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:Type: vm ioctl
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:Parameters: struct kvm_dirty_log (in/out)
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:Returns: 0 on success, -1 on error
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::
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/* for KVM_GET_DIRTY_LOG */
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struct kvm_dirty_log {
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__u32 slot;
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__u32 padding;
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union {
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void __user *dirty_bitmap; /* one bit per page */
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__u64 padding;
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};
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};
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Given a memory slot, return a bitmap containing any pages dirtied
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since the last call to this ioctl. Bit 0 is the first page in the
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memory slot. Ensure the entire structure is cleared to avoid padding
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issues.
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If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of slot field specifies
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the address space for which you want to return the dirty bitmap. See
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KVM_SET_USER_MEMORY_REGION for details on the usage of slot field.
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The bits in the dirty bitmap are cleared before the ioctl returns, unless
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KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is enabled. For more information,
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see the description of the capability.
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Note that the Xen shared info page, if configured, shall always be assumed
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to be dirty. KVM will not explicitly mark it such.
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4.9 KVM_SET_MEMORY_ALIAS
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------------------------
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:Capability: basic
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:Architectures: x86
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:Type: vm ioctl
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:Parameters: struct kvm_memory_alias (in)
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:Returns: 0 (success), -1 (error)
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This ioctl is obsolete and has been removed.
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4.10 KVM_RUN
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------------
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:Capability: basic
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:Architectures: all
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:Type: vcpu ioctl
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:Parameters: none
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:Returns: 0 on success, -1 on error
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Errors:
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======= ==============================================================
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EINTR an unmasked signal is pending
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ENOEXEC the vcpu hasn't been initialized or the guest tried to execute
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instructions from device memory (arm64)
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ENOSYS data abort outside memslots with no syndrome info and
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KVM_CAP_ARM_NISV_TO_USER not enabled (arm64)
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EPERM SVE feature set but not finalized (arm64)
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======= ==============================================================
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This ioctl is used to run a guest virtual cpu. While there are no
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explicit parameters, there is an implicit parameter block that can be
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obtained by mmap()ing the vcpu fd at offset 0, with the size given by
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KVM_GET_VCPU_MMAP_SIZE. The parameter block is formatted as a 'struct
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kvm_run' (see below).
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4.11 KVM_GET_REGS
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-----------------
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:Capability: basic
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:Architectures: all except arm64
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:Type: vcpu ioctl
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:Parameters: struct kvm_regs (out)
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:Returns: 0 on success, -1 on error
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Reads the general purpose registers from the vcpu.
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::
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/* x86 */
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struct kvm_regs {
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/* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
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__u64 rax, rbx, rcx, rdx;
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__u64 rsi, rdi, rsp, rbp;
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__u64 r8, r9, r10, r11;
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__u64 r12, r13, r14, r15;
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__u64 rip, rflags;
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};
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/* mips */
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struct kvm_regs {
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/* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
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__u64 gpr[32];
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__u64 hi;
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__u64 lo;
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__u64 pc;
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};
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4.12 KVM_SET_REGS
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-----------------
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:Capability: basic
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:Architectures: all except arm64
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:Type: vcpu ioctl
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:Parameters: struct kvm_regs (in)
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:Returns: 0 on success, -1 on error
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Writes the general purpose registers into the vcpu.
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See KVM_GET_REGS for the data structure.
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4.13 KVM_GET_SREGS
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------------------
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:Capability: basic
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:Architectures: x86, ppc
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:Type: vcpu ioctl
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:Parameters: struct kvm_sregs (out)
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:Returns: 0 on success, -1 on error
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Reads special registers from the vcpu.
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::
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/* x86 */
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struct kvm_sregs {
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struct kvm_segment cs, ds, es, fs, gs, ss;
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struct kvm_segment tr, ldt;
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struct kvm_dtable gdt, idt;
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__u64 cr0, cr2, cr3, cr4, cr8;
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__u64 efer;
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__u64 apic_base;
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__u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64];
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};
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/* ppc -- see arch/powerpc/include/uapi/asm/kvm.h */
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interrupt_bitmap is a bitmap of pending external interrupts. At most
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one bit may be set. This interrupt has been acknowledged by the APIC
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but not yet injected into the cpu core.
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4.14 KVM_SET_SREGS
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------------------
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:Capability: basic
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:Architectures: x86, ppc
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:Type: vcpu ioctl
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:Parameters: struct kvm_sregs (in)
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:Returns: 0 on success, -1 on error
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Writes special registers into the vcpu. See KVM_GET_SREGS for the
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data structures.
|
|
|
|
|
|
4.15 KVM_TRANSLATE
|
|
------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_translation (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Translates a virtual address according to the vcpu's current address
|
|
translation mode.
|
|
|
|
::
|
|
|
|
struct kvm_translation {
|
|
/* in */
|
|
__u64 linear_address;
|
|
|
|
/* out */
|
|
__u64 physical_address;
|
|
__u8 valid;
|
|
__u8 writeable;
|
|
__u8 usermode;
|
|
__u8 pad[5];
|
|
};
|
|
|
|
|
|
4.16 KVM_INTERRUPT
|
|
------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86, ppc, mips, riscv
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_interrupt (in)
|
|
:Returns: 0 on success, negative on failure.
|
|
|
|
Queues a hardware interrupt vector to be injected.
|
|
|
|
::
|
|
|
|
/* for KVM_INTERRUPT */
|
|
struct kvm_interrupt {
|
|
/* in */
|
|
__u32 irq;
|
|
};
|
|
|
|
X86:
|
|
^^^^
|
|
|
|
:Returns:
|
|
|
|
========= ===================================
|
|
0 on success,
|
|
-EEXIST if an interrupt is already enqueued
|
|
-EINVAL the irq number is invalid
|
|
-ENXIO if the PIC is in the kernel
|
|
-EFAULT if the pointer is invalid
|
|
========= ===================================
|
|
|
|
Note 'irq' is an interrupt vector, not an interrupt pin or line. This
|
|
ioctl is useful if the in-kernel PIC is not used.
|
|
|
|
PPC:
|
|
^^^^
|
|
|
|
Queues an external interrupt to be injected. This ioctl is overleaded
|
|
with 3 different irq values:
|
|
|
|
a) KVM_INTERRUPT_SET
|
|
|
|
This injects an edge type external interrupt into the guest once it's ready
|
|
to receive interrupts. When injected, the interrupt is done.
|
|
|
|
b) KVM_INTERRUPT_UNSET
|
|
|
|
This unsets any pending interrupt.
|
|
|
|
Only available with KVM_CAP_PPC_UNSET_IRQ.
|
|
|
|
c) KVM_INTERRUPT_SET_LEVEL
|
|
|
|
This injects a level type external interrupt into the guest context. The
|
|
interrupt stays pending until a specific ioctl with KVM_INTERRUPT_UNSET
|
|
is triggered.
|
|
|
|
Only available with KVM_CAP_PPC_IRQ_LEVEL.
|
|
|
|
Note that any value for 'irq' other than the ones stated above is invalid
|
|
and incurs unexpected behavior.
|
|
|
|
This is an asynchronous vcpu ioctl and can be invoked from any thread.
|
|
|
|
MIPS:
|
|
^^^^^
|
|
|
|
Queues an external interrupt to be injected into the virtual CPU. A negative
|
|
interrupt number dequeues the interrupt.
|
|
|
|
This is an asynchronous vcpu ioctl and can be invoked from any thread.
|
|
|
|
RISC-V:
|
|
^^^^^^^
|
|
|
|
Queues an external interrupt to be injected into the virutal CPU. This ioctl
|
|
is overloaded with 2 different irq values:
|
|
|
|
a) KVM_INTERRUPT_SET
|
|
|
|
This sets external interrupt for a virtual CPU and it will receive
|
|
once it is ready.
|
|
|
|
b) KVM_INTERRUPT_UNSET
|
|
|
|
This clears pending external interrupt for a virtual CPU.
|
|
|
|
This is an asynchronous vcpu ioctl and can be invoked from any thread.
|
|
|
|
|
|
4.17 KVM_DEBUG_GUEST
|
|
--------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: none
|
|
:Type: vcpu ioctl
|
|
:Parameters: none)
|
|
:Returns: -1 on error
|
|
|
|
Support for this has been removed. Use KVM_SET_GUEST_DEBUG instead.
|
|
|
|
|
|
4.18 KVM_GET_MSRS
|
|
-----------------
|
|
|
|
:Capability: basic (vcpu), KVM_CAP_GET_MSR_FEATURES (system)
|
|
:Architectures: x86
|
|
:Type: system ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_msrs (in/out)
|
|
:Returns: number of msrs successfully returned;
|
|
-1 on error
|
|
|
|
When used as a system ioctl:
|
|
Reads the values of MSR-based features that are available for the VM. This
|
|
is similar to KVM_GET_SUPPORTED_CPUID, but it returns MSR indices and values.
|
|
The list of msr-based features can be obtained using KVM_GET_MSR_FEATURE_INDEX_LIST
|
|
in a system ioctl.
|
|
|
|
When used as a vcpu ioctl:
|
|
Reads model-specific registers from the vcpu. Supported msr indices can
|
|
be obtained using KVM_GET_MSR_INDEX_LIST in a system ioctl.
|
|
|
|
::
|
|
|
|
struct kvm_msrs {
|
|
__u32 nmsrs; /* number of msrs in entries */
|
|
__u32 pad;
|
|
|
|
struct kvm_msr_entry entries[0];
|
|
};
|
|
|
|
struct kvm_msr_entry {
|
|
__u32 index;
|
|
__u32 reserved;
|
|
__u64 data;
|
|
};
|
|
|
|
Application code should set the 'nmsrs' member (which indicates the
|
|
size of the entries array) and the 'index' member of each array entry.
|
|
kvm will fill in the 'data' member.
|
|
|
|
|
|
4.19 KVM_SET_MSRS
|
|
-----------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_msrs (in)
|
|
:Returns: number of msrs successfully set (see below), -1 on error
|
|
|
|
Writes model-specific registers to the vcpu. See KVM_GET_MSRS for the
|
|
data structures.
|
|
|
|
Application code should set the 'nmsrs' member (which indicates the
|
|
size of the entries array), and the 'index' and 'data' members of each
|
|
array entry.
|
|
|
|
It tries to set the MSRs in array entries[] one by one. If setting an MSR
|
|
fails, e.g., due to setting reserved bits, the MSR isn't supported/emulated
|
|
by KVM, etc..., it stops processing the MSR list and returns the number of
|
|
MSRs that have been set successfully.
|
|
|
|
|
|
4.20 KVM_SET_CPUID
|
|
------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_cpuid (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Defines the vcpu responses to the cpuid instruction. Applications
|
|
should use the KVM_SET_CPUID2 ioctl if available.
|
|
|
|
Caveat emptor:
|
|
- If this IOCTL fails, KVM gives no guarantees that previous valid CPUID
|
|
configuration (if there is) is not corrupted. Userspace can get a copy
|
|
of the resulting CPUID configuration through KVM_GET_CPUID2 in case.
|
|
- Using KVM_SET_CPUID{,2} after KVM_RUN, i.e. changing the guest vCPU model
|
|
after running the guest, may cause guest instability.
|
|
- Using heterogeneous CPUID configurations, modulo APIC IDs, topology, etc...
|
|
may cause guest instability.
|
|
|
|
::
|
|
|
|
struct kvm_cpuid_entry {
|
|
__u32 function;
|
|
__u32 eax;
|
|
__u32 ebx;
|
|
__u32 ecx;
|
|
__u32 edx;
|
|
__u32 padding;
|
|
};
|
|
|
|
/* for KVM_SET_CPUID */
|
|
struct kvm_cpuid {
|
|
__u32 nent;
|
|
__u32 padding;
|
|
struct kvm_cpuid_entry entries[0];
|
|
};
|
|
|
|
|
|
4.21 KVM_SET_SIGNAL_MASK
|
|
------------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: all
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_signal_mask (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Defines which signals are blocked during execution of KVM_RUN. This
|
|
signal mask temporarily overrides the threads signal mask. Any
|
|
unblocked signal received (except SIGKILL and SIGSTOP, which retain
|
|
their traditional behaviour) will cause KVM_RUN to return with -EINTR.
|
|
|
|
Note the signal will only be delivered if not blocked by the original
|
|
signal mask.
|
|
|
|
::
|
|
|
|
/* for KVM_SET_SIGNAL_MASK */
|
|
struct kvm_signal_mask {
|
|
__u32 len;
|
|
__u8 sigset[0];
|
|
};
|
|
|
|
|
|
4.22 KVM_GET_FPU
|
|
----------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_fpu (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Reads the floating point state from the vcpu.
|
|
|
|
::
|
|
|
|
/* for KVM_GET_FPU and KVM_SET_FPU */
|
|
struct kvm_fpu {
|
|
__u8 fpr[8][16];
|
|
__u16 fcw;
|
|
__u16 fsw;
|
|
__u8 ftwx; /* in fxsave format */
|
|
__u8 pad1;
|
|
__u16 last_opcode;
|
|
__u64 last_ip;
|
|
__u64 last_dp;
|
|
__u8 xmm[16][16];
|
|
__u32 mxcsr;
|
|
__u32 pad2;
|
|
};
|
|
|
|
|
|
4.23 KVM_SET_FPU
|
|
----------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_fpu (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Writes the floating point state to the vcpu.
|
|
|
|
::
|
|
|
|
/* for KVM_GET_FPU and KVM_SET_FPU */
|
|
struct kvm_fpu {
|
|
__u8 fpr[8][16];
|
|
__u16 fcw;
|
|
__u16 fsw;
|
|
__u8 ftwx; /* in fxsave format */
|
|
__u8 pad1;
|
|
__u16 last_opcode;
|
|
__u64 last_ip;
|
|
__u64 last_dp;
|
|
__u8 xmm[16][16];
|
|
__u32 mxcsr;
|
|
__u32 pad2;
|
|
};
|
|
|
|
|
|
4.24 KVM_CREATE_IRQCHIP
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP, KVM_CAP_S390_IRQCHIP (s390)
|
|
:Architectures: x86, arm64, s390
|
|
:Type: vm ioctl
|
|
:Parameters: none
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Creates an interrupt controller model in the kernel.
|
|
On x86, creates a virtual ioapic, a virtual PIC (two PICs, nested), and sets up
|
|
future vcpus to have a local APIC. IRQ routing for GSIs 0-15 is set to both
|
|
PIC and IOAPIC; GSI 16-23 only go to the IOAPIC.
|
|
On arm64, a GICv2 is created. Any other GIC versions require the usage of
|
|
KVM_CREATE_DEVICE, which also supports creating a GICv2. Using
|
|
KVM_CREATE_DEVICE is preferred over KVM_CREATE_IRQCHIP for GICv2.
|
|
On s390, a dummy irq routing table is created.
|
|
|
|
Note that on s390 the KVM_CAP_S390_IRQCHIP vm capability needs to be enabled
|
|
before KVM_CREATE_IRQCHIP can be used.
|
|
|
|
|
|
4.25 KVM_IRQ_LINE
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP
|
|
:Architectures: x86, arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irq_level
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the level of a GSI input to the interrupt controller model in the kernel.
|
|
On some architectures it is required that an interrupt controller model has
|
|
been previously created with KVM_CREATE_IRQCHIP. Note that edge-triggered
|
|
interrupts require the level to be set to 1 and then back to 0.
|
|
|
|
On real hardware, interrupt pins can be active-low or active-high. This
|
|
does not matter for the level field of struct kvm_irq_level: 1 always
|
|
means active (asserted), 0 means inactive (deasserted).
|
|
|
|
x86 allows the operating system to program the interrupt polarity
|
|
(active-low/active-high) for level-triggered interrupts, and KVM used
|
|
to consider the polarity. However, due to bitrot in the handling of
|
|
active-low interrupts, the above convention is now valid on x86 too.
|
|
This is signaled by KVM_CAP_X86_IOAPIC_POLARITY_IGNORED. Userspace
|
|
should not present interrupts to the guest as active-low unless this
|
|
capability is present (or unless it is not using the in-kernel irqchip,
|
|
of course).
|
|
|
|
|
|
arm64 can signal an interrupt either at the CPU level, or at the
|
|
in-kernel irqchip (GIC), and for in-kernel irqchip can tell the GIC to
|
|
use PPIs designated for specific cpus. The irq field is interpreted
|
|
like this::
|
|
|
|
bits: | 31 ... 28 | 27 ... 24 | 23 ... 16 | 15 ... 0 |
|
|
field: | vcpu2_index | irq_type | vcpu_index | irq_id |
|
|
|
|
The irq_type field has the following values:
|
|
|
|
- irq_type[0]:
|
|
out-of-kernel GIC: irq_id 0 is IRQ, irq_id 1 is FIQ
|
|
- irq_type[1]:
|
|
in-kernel GIC: SPI, irq_id between 32 and 1019 (incl.)
|
|
(the vcpu_index field is ignored)
|
|
- irq_type[2]:
|
|
in-kernel GIC: PPI, irq_id between 16 and 31 (incl.)
|
|
|
|
(The irq_id field thus corresponds nicely to the IRQ ID in the ARM GIC specs)
|
|
|
|
In both cases, level is used to assert/deassert the line.
|
|
|
|
When KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 is supported, the target vcpu is
|
|
identified as (256 * vcpu2_index + vcpu_index). Otherwise, vcpu2_index
|
|
must be zero.
|
|
|
|
Note that on arm64, the KVM_CAP_IRQCHIP capability only conditions
|
|
injection of interrupts for the in-kernel irqchip. KVM_IRQ_LINE can always
|
|
be used for a userspace interrupt controller.
|
|
|
|
::
|
|
|
|
struct kvm_irq_level {
|
|
union {
|
|
__u32 irq; /* GSI */
|
|
__s32 status; /* not used for KVM_IRQ_LEVEL */
|
|
};
|
|
__u32 level; /* 0 or 1 */
|
|
};
|
|
|
|
|
|
4.26 KVM_GET_IRQCHIP
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irqchip (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Reads the state of a kernel interrupt controller created with
|
|
KVM_CREATE_IRQCHIP into a buffer provided by the caller.
|
|
|
|
::
|
|
|
|
struct kvm_irqchip {
|
|
__u32 chip_id; /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
|
|
__u32 pad;
|
|
union {
|
|
char dummy[512]; /* reserving space */
|
|
struct kvm_pic_state pic;
|
|
struct kvm_ioapic_state ioapic;
|
|
} chip;
|
|
};
|
|
|
|
|
|
4.27 KVM_SET_IRQCHIP
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irqchip (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the state of a kernel interrupt controller created with
|
|
KVM_CREATE_IRQCHIP from a buffer provided by the caller.
|
|
|
|
::
|
|
|
|
struct kvm_irqchip {
|
|
__u32 chip_id; /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
|
|
__u32 pad;
|
|
union {
|
|
char dummy[512]; /* reserving space */
|
|
struct kvm_pic_state pic;
|
|
struct kvm_ioapic_state ioapic;
|
|
} chip;
|
|
};
|
|
|
|
|
|
4.28 KVM_XEN_HVM_CONFIG
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_xen_hvm_config (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the MSR that the Xen HVM guest uses to initialize its hypercall
|
|
page, and provides the starting address and size of the hypercall
|
|
blobs in userspace. When the guest writes the MSR, kvm copies one
|
|
page of a blob (32- or 64-bit, depending on the vcpu mode) to guest
|
|
memory.
|
|
|
|
::
|
|
|
|
struct kvm_xen_hvm_config {
|
|
__u32 flags;
|
|
__u32 msr;
|
|
__u64 blob_addr_32;
|
|
__u64 blob_addr_64;
|
|
__u8 blob_size_32;
|
|
__u8 blob_size_64;
|
|
__u8 pad2[30];
|
|
};
|
|
|
|
If certain flags are returned from the KVM_CAP_XEN_HVM check, they may
|
|
be set in the flags field of this ioctl:
|
|
|
|
The KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL flag requests KVM to generate
|
|
the contents of the hypercall page automatically; hypercalls will be
|
|
intercepted and passed to userspace through KVM_EXIT_XEN. In this
|
|
ase, all of the blob size and address fields must be zero.
|
|
|
|
The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indicates to KVM that userspace
|
|
will always use the KVM_XEN_HVM_EVTCHN_SEND ioctl to deliver event
|
|
channel interrupts rather than manipulating the guest's shared_info
|
|
structures directly. This, in turn, may allow KVM to enable features
|
|
such as intercepting the SCHEDOP_poll hypercall to accelerate PV
|
|
spinlock operation for the guest. Userspace may still use the ioctl
|
|
to deliver events if it was advertised, even if userspace does not
|
|
send this indication that it will always do so
|
|
|
|
No other flags are currently valid in the struct kvm_xen_hvm_config.
|
|
|
|
4.29 KVM_GET_CLOCK
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_ADJUST_CLOCK
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_clock_data (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Gets the current timestamp of kvmclock as seen by the current guest. In
|
|
conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios
|
|
such as migration.
|
|
|
|
When KVM_CAP_ADJUST_CLOCK is passed to KVM_CHECK_EXTENSION, it returns the
|
|
set of bits that KVM can return in struct kvm_clock_data's flag member.
|
|
|
|
The following flags are defined:
|
|
|
|
KVM_CLOCK_TSC_STABLE
|
|
If set, the returned value is the exact kvmclock
|
|
value seen by all VCPUs at the instant when KVM_GET_CLOCK was called.
|
|
If clear, the returned value is simply CLOCK_MONOTONIC plus a constant
|
|
offset; the offset can be modified with KVM_SET_CLOCK. KVM will try
|
|
to make all VCPUs follow this clock, but the exact value read by each
|
|
VCPU could differ, because the host TSC is not stable.
|
|
|
|
KVM_CLOCK_REALTIME
|
|
If set, the `realtime` field in the kvm_clock_data
|
|
structure is populated with the value of the host's real time
|
|
clocksource at the instant when KVM_GET_CLOCK was called. If clear,
|
|
the `realtime` field does not contain a value.
|
|
|
|
KVM_CLOCK_HOST_TSC
|
|
If set, the `host_tsc` field in the kvm_clock_data
|
|
structure is populated with the value of the host's timestamp counter (TSC)
|
|
at the instant when KVM_GET_CLOCK was called. If clear, the `host_tsc` field
|
|
does not contain a value.
|
|
|
|
::
|
|
|
|
struct kvm_clock_data {
|
|
__u64 clock; /* kvmclock current value */
|
|
__u32 flags;
|
|
__u32 pad0;
|
|
__u64 realtime;
|
|
__u64 host_tsc;
|
|
__u32 pad[4];
|
|
};
|
|
|
|
|
|
4.30 KVM_SET_CLOCK
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_ADJUST_CLOCK
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_clock_data (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the current timestamp of kvmclock to the value specified in its parameter.
|
|
In conjunction with KVM_GET_CLOCK, it is used to ensure monotonicity on scenarios
|
|
such as migration.
|
|
|
|
The following flags can be passed:
|
|
|
|
KVM_CLOCK_REALTIME
|
|
If set, KVM will compare the value of the `realtime` field
|
|
with the value of the host's real time clocksource at the instant when
|
|
KVM_SET_CLOCK was called. The difference in elapsed time is added to the final
|
|
kvmclock value that will be provided to guests.
|
|
|
|
Other flags returned by ``KVM_GET_CLOCK`` are accepted but ignored.
|
|
|
|
::
|
|
|
|
struct kvm_clock_data {
|
|
__u64 clock; /* kvmclock current value */
|
|
__u32 flags;
|
|
__u32 pad0;
|
|
__u64 realtime;
|
|
__u64 host_tsc;
|
|
__u32 pad[4];
|
|
};
|
|
|
|
|
|
4.31 KVM_GET_VCPU_EVENTS
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_VCPU_EVENTS
|
|
:Extended by: KVM_CAP_INTR_SHADOW
|
|
:Architectures: x86, arm64
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_vcpu_event (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
X86:
|
|
^^^^
|
|
|
|
Gets currently pending exceptions, interrupts, and NMIs as well as related
|
|
states of the vcpu.
|
|
|
|
::
|
|
|
|
struct kvm_vcpu_events {
|
|
struct {
|
|
__u8 injected;
|
|
__u8 nr;
|
|
__u8 has_error_code;
|
|
__u8 pending;
|
|
__u32 error_code;
|
|
} exception;
|
|
struct {
|
|
__u8 injected;
|
|
__u8 nr;
|
|
__u8 soft;
|
|
__u8 shadow;
|
|
} interrupt;
|
|
struct {
|
|
__u8 injected;
|
|
__u8 pending;
|
|
__u8 masked;
|
|
__u8 pad;
|
|
} nmi;
|
|
__u32 sipi_vector;
|
|
__u32 flags;
|
|
struct {
|
|
__u8 smm;
|
|
__u8 pending;
|
|
__u8 smm_inside_nmi;
|
|
__u8 latched_init;
|
|
} smi;
|
|
__u8 reserved[27];
|
|
__u8 exception_has_payload;
|
|
__u64 exception_payload;
|
|
};
|
|
|
|
The following bits are defined in the flags field:
|
|
|
|
- KVM_VCPUEVENT_VALID_SHADOW may be set to signal that
|
|
interrupt.shadow contains a valid state.
|
|
|
|
- KVM_VCPUEVENT_VALID_SMM may be set to signal that smi contains a
|
|
valid state.
|
|
|
|
- KVM_VCPUEVENT_VALID_PAYLOAD may be set to signal that the
|
|
exception_has_payload, exception_payload, and exception.pending
|
|
fields contain a valid state. This bit will be set whenever
|
|
KVM_CAP_EXCEPTION_PAYLOAD is enabled.
|
|
|
|
- KVM_VCPUEVENT_VALID_TRIPLE_FAULT may be set to signal that the
|
|
triple_fault_pending field contains a valid state. This bit will
|
|
be set whenever KVM_CAP_X86_TRIPLE_FAULT_EVENT is enabled.
|
|
|
|
ARM64:
|
|
^^^^^^
|
|
|
|
If the guest accesses a device that is being emulated by the host kernel in
|
|
such a way that a real device would generate a physical SError, KVM may make
|
|
a virtual SError pending for that VCPU. This system error interrupt remains
|
|
pending until the guest takes the exception by unmasking PSTATE.A.
|
|
|
|
Running the VCPU may cause it to take a pending SError, or make an access that
|
|
causes an SError to become pending. The event's description is only valid while
|
|
the VPCU is not running.
|
|
|
|
This API provides a way to read and write the pending 'event' state that is not
|
|
visible to the guest. To save, restore or migrate a VCPU the struct representing
|
|
the state can be read then written using this GET/SET API, along with the other
|
|
guest-visible registers. It is not possible to 'cancel' an SError that has been
|
|
made pending.
|
|
|
|
A device being emulated in user-space may also wish to generate an SError. To do
|
|
this the events structure can be populated by user-space. The current state
|
|
should be read first, to ensure no existing SError is pending. If an existing
|
|
SError is pending, the architecture's 'Multiple SError interrupts' rules should
|
|
be followed. (2.5.3 of DDI0587.a "ARM Reliability, Availability, and
|
|
Serviceability (RAS) Specification").
|
|
|
|
SError exceptions always have an ESR value. Some CPUs have the ability to
|
|
specify what the virtual SError's ESR value should be. These systems will
|
|
advertise KVM_CAP_ARM_INJECT_SERROR_ESR. In this case exception.has_esr will
|
|
always have a non-zero value when read, and the agent making an SError pending
|
|
should specify the ISS field in the lower 24 bits of exception.serror_esr. If
|
|
the system supports KVM_CAP_ARM_INJECT_SERROR_ESR, but user-space sets the events
|
|
with exception.has_esr as zero, KVM will choose an ESR.
|
|
|
|
Specifying exception.has_esr on a system that does not support it will return
|
|
-EINVAL. Setting anything other than the lower 24bits of exception.serror_esr
|
|
will return -EINVAL.
|
|
|
|
It is not possible to read back a pending external abort (injected via
|
|
KVM_SET_VCPU_EVENTS or otherwise) because such an exception is always delivered
|
|
directly to the virtual CPU).
|
|
|
|
::
|
|
|
|
struct kvm_vcpu_events {
|
|
struct {
|
|
__u8 serror_pending;
|
|
__u8 serror_has_esr;
|
|
__u8 ext_dabt_pending;
|
|
/* Align it to 8 bytes */
|
|
__u8 pad[5];
|
|
__u64 serror_esr;
|
|
} exception;
|
|
__u32 reserved[12];
|
|
};
|
|
|
|
4.32 KVM_SET_VCPU_EVENTS
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_VCPU_EVENTS
|
|
:Extended by: KVM_CAP_INTR_SHADOW
|
|
:Architectures: x86, arm64
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_vcpu_event (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
X86:
|
|
^^^^
|
|
|
|
Set pending exceptions, interrupts, and NMIs as well as related states of the
|
|
vcpu.
|
|
|
|
See KVM_GET_VCPU_EVENTS for the data structure.
|
|
|
|
Fields that may be modified asynchronously by running VCPUs can be excluded
|
|
from the update. These fields are nmi.pending, sipi_vector, smi.smm,
|
|
smi.pending. Keep the corresponding bits in the flags field cleared to
|
|
suppress overwriting the current in-kernel state. The bits are:
|
|
|
|
=============================== ==================================
|
|
KVM_VCPUEVENT_VALID_NMI_PENDING transfer nmi.pending to the kernel
|
|
KVM_VCPUEVENT_VALID_SIPI_VECTOR transfer sipi_vector
|
|
KVM_VCPUEVENT_VALID_SMM transfer the smi sub-struct.
|
|
=============================== ==================================
|
|
|
|
If KVM_CAP_INTR_SHADOW is available, KVM_VCPUEVENT_VALID_SHADOW can be set in
|
|
the flags field to signal that interrupt.shadow contains a valid state and
|
|
shall be written into the VCPU.
|
|
|
|
KVM_VCPUEVENT_VALID_SMM can only be set if KVM_CAP_X86_SMM is available.
|
|
|
|
If KVM_CAP_EXCEPTION_PAYLOAD is enabled, KVM_VCPUEVENT_VALID_PAYLOAD
|
|
can be set in the flags field to signal that the
|
|
exception_has_payload, exception_payload, and exception.pending fields
|
|
contain a valid state and shall be written into the VCPU.
|
|
|
|
If KVM_CAP_X86_TRIPLE_FAULT_EVENT is enabled, KVM_VCPUEVENT_VALID_TRIPLE_FAULT
|
|
can be set in flags field to signal that the triple_fault field contains
|
|
a valid state and shall be written into the VCPU.
|
|
|
|
ARM64:
|
|
^^^^^^
|
|
|
|
User space may need to inject several types of events to the guest.
|
|
|
|
Set the pending SError exception state for this VCPU. It is not possible to
|
|
'cancel' an Serror that has been made pending.
|
|
|
|
If the guest performed an access to I/O memory which could not be handled by
|
|
userspace, for example because of missing instruction syndrome decode
|
|
information or because there is no device mapped at the accessed IPA, then
|
|
userspace can ask the kernel to inject an external abort using the address
|
|
from the exiting fault on the VCPU. It is a programming error to set
|
|
ext_dabt_pending after an exit which was not either KVM_EXIT_MMIO or
|
|
KVM_EXIT_ARM_NISV. This feature is only available if the system supports
|
|
KVM_CAP_ARM_INJECT_EXT_DABT. This is a helper which provides commonality in
|
|
how userspace reports accesses for the above cases to guests, across different
|
|
userspace implementations. Nevertheless, userspace can still emulate all Arm
|
|
exceptions by manipulating individual registers using the KVM_SET_ONE_REG API.
|
|
|
|
See KVM_GET_VCPU_EVENTS for the data structure.
|
|
|
|
|
|
4.33 KVM_GET_DEBUGREGS
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_DEBUGREGS
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_debugregs (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Reads debug registers from the vcpu.
|
|
|
|
::
|
|
|
|
struct kvm_debugregs {
|
|
__u64 db[4];
|
|
__u64 dr6;
|
|
__u64 dr7;
|
|
__u64 flags;
|
|
__u64 reserved[9];
|
|
};
|
|
|
|
|
|
4.34 KVM_SET_DEBUGREGS
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_DEBUGREGS
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_debugregs (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Writes debug registers into the vcpu.
|
|
|
|
See KVM_GET_DEBUGREGS for the data structure. The flags field is unused
|
|
yet and must be cleared on entry.
|
|
|
|
|
|
4.35 KVM_SET_USER_MEMORY_REGION
|
|
-------------------------------
|
|
|
|
:Capability: KVM_CAP_USER_MEMORY
|
|
:Architectures: all
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_userspace_memory_region (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_userspace_memory_region {
|
|
__u32 slot;
|
|
__u32 flags;
|
|
__u64 guest_phys_addr;
|
|
__u64 memory_size; /* bytes */
|
|
__u64 userspace_addr; /* start of the userspace allocated memory */
|
|
};
|
|
|
|
/* for kvm_memory_region::flags */
|
|
#define KVM_MEM_LOG_DIRTY_PAGES (1UL << 0)
|
|
#define KVM_MEM_READONLY (1UL << 1)
|
|
|
|
This ioctl allows the user to create, modify or delete a guest physical
|
|
memory slot. Bits 0-15 of "slot" specify the slot id and this value
|
|
should be less than the maximum number of user memory slots supported per
|
|
VM. The maximum allowed slots can be queried using KVM_CAP_NR_MEMSLOTS.
|
|
Slots may not overlap in guest physical address space.
|
|
|
|
If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of "slot"
|
|
specifies the address space which is being modified. They must be
|
|
less than the value that KVM_CHECK_EXTENSION returns for the
|
|
KVM_CAP_MULTI_ADDRESS_SPACE capability. Slots in separate address spaces
|
|
are unrelated; the restriction on overlapping slots only applies within
|
|
each address space.
|
|
|
|
Deleting a slot is done by passing zero for memory_size. When changing
|
|
an existing slot, it may be moved in the guest physical memory space,
|
|
or its flags may be modified, but it may not be resized.
|
|
|
|
Memory for the region is taken starting at the address denoted by the
|
|
field userspace_addr, which must point at user addressable memory for
|
|
the entire memory slot size. Any object may back this memory, including
|
|
anonymous memory, ordinary files, and hugetlbfs.
|
|
|
|
On architectures that support a form of address tagging, userspace_addr must
|
|
be an untagged address.
|
|
|
|
It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr
|
|
be identical. This allows large pages in the guest to be backed by large
|
|
pages in the host.
|
|
|
|
The flags field supports two flags: KVM_MEM_LOG_DIRTY_PAGES and
|
|
KVM_MEM_READONLY. The former can be set to instruct KVM to keep track of
|
|
writes to memory within the slot. See KVM_GET_DIRTY_LOG ioctl to know how to
|
|
use it. The latter can be set, if KVM_CAP_READONLY_MEM capability allows it,
|
|
to make a new slot read-only. In this case, writes to this memory will be
|
|
posted to userspace as KVM_EXIT_MMIO exits.
|
|
|
|
When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of
|
|
the memory region are automatically reflected into the guest. For example, an
|
|
mmap() that affects the region will be made visible immediately. Another
|
|
example is madvise(MADV_DROP).
|
|
|
|
It is recommended to use this API instead of the KVM_SET_MEMORY_REGION ioctl.
|
|
The KVM_SET_MEMORY_REGION does not allow fine grained control over memory
|
|
allocation and is deprecated.
|
|
|
|
|
|
4.36 KVM_SET_TSS_ADDR
|
|
---------------------
|
|
|
|
:Capability: KVM_CAP_SET_TSS_ADDR
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: unsigned long tss_address (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This ioctl defines the physical address of a three-page region in the guest
|
|
physical address space. The region must be within the first 4GB of the
|
|
guest physical address space and must not conflict with any memory slot
|
|
or any mmio address. The guest may malfunction if it accesses this memory
|
|
region.
|
|
|
|
This ioctl is required on Intel-based hosts. This is needed on Intel hardware
|
|
because of a quirk in the virtualization implementation (see the internals
|
|
documentation when it pops into existence).
|
|
|
|
|
|
4.37 KVM_ENABLE_CAP
|
|
-------------------
|
|
|
|
:Capability: KVM_CAP_ENABLE_CAP
|
|
:Architectures: mips, ppc, s390, x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_enable_cap (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
:Capability: KVM_CAP_ENABLE_CAP_VM
|
|
:Architectures: all
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_enable_cap (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
.. note::
|
|
|
|
Not all extensions are enabled by default. Using this ioctl the application
|
|
can enable an extension, making it available to the guest.
|
|
|
|
On systems that do not support this ioctl, it always fails. On systems that
|
|
do support it, it only works for extensions that are supported for enablement.
|
|
|
|
To check if a capability can be enabled, the KVM_CHECK_EXTENSION ioctl should
|
|
be used.
|
|
|
|
::
|
|
|
|
struct kvm_enable_cap {
|
|
/* in */
|
|
__u32 cap;
|
|
|
|
The capability that is supposed to get enabled.
|
|
|
|
::
|
|
|
|
__u32 flags;
|
|
|
|
A bitfield indicating future enhancements. Has to be 0 for now.
|
|
|
|
::
|
|
|
|
__u64 args[4];
|
|
|
|
Arguments for enabling a feature. If a feature needs initial values to
|
|
function properly, this is the place to put them.
|
|
|
|
::
|
|
|
|
__u8 pad[64];
|
|
};
|
|
|
|
The vcpu ioctl should be used for vcpu-specific capabilities, the vm ioctl
|
|
for vm-wide capabilities.
|
|
|
|
4.38 KVM_GET_MP_STATE
|
|
---------------------
|
|
|
|
:Capability: KVM_CAP_MP_STATE
|
|
:Architectures: x86, s390, arm64, riscv
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_mp_state (out)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_mp_state {
|
|
__u32 mp_state;
|
|
};
|
|
|
|
Returns the vcpu's current "multiprocessing state" (though also valid on
|
|
uniprocessor guests).
|
|
|
|
Possible values are:
|
|
|
|
========================== ===============================================
|
|
KVM_MP_STATE_RUNNABLE the vcpu is currently running
|
|
[x86,arm64,riscv]
|
|
KVM_MP_STATE_UNINITIALIZED the vcpu is an application processor (AP)
|
|
which has not yet received an INIT signal [x86]
|
|
KVM_MP_STATE_INIT_RECEIVED the vcpu has received an INIT signal, and is
|
|
now ready for a SIPI [x86]
|
|
KVM_MP_STATE_HALTED the vcpu has executed a HLT instruction and
|
|
is waiting for an interrupt [x86]
|
|
KVM_MP_STATE_SIPI_RECEIVED the vcpu has just received a SIPI (vector
|
|
accessible via KVM_GET_VCPU_EVENTS) [x86]
|
|
KVM_MP_STATE_STOPPED the vcpu is stopped [s390,arm64,riscv]
|
|
KVM_MP_STATE_CHECK_STOP the vcpu is in a special error state [s390]
|
|
KVM_MP_STATE_OPERATING the vcpu is operating (running or halted)
|
|
[s390]
|
|
KVM_MP_STATE_LOAD the vcpu is in a special load/startup state
|
|
[s390]
|
|
KVM_MP_STATE_SUSPENDED the vcpu is in a suspend state and is waiting
|
|
for a wakeup event [arm64]
|
|
========================== ===============================================
|
|
|
|
On x86, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an
|
|
in-kernel irqchip, the multiprocessing state must be maintained by userspace on
|
|
these architectures.
|
|
|
|
For arm64:
|
|
^^^^^^^^^^
|
|
|
|
If a vCPU is in the KVM_MP_STATE_SUSPENDED state, KVM will emulate the
|
|
architectural execution of a WFI instruction.
|
|
|
|
If a wakeup event is recognized, KVM will exit to userspace with a
|
|
KVM_SYSTEM_EVENT exit, where the event type is KVM_SYSTEM_EVENT_WAKEUP. If
|
|
userspace wants to honor the wakeup, it must set the vCPU's MP state to
|
|
KVM_MP_STATE_RUNNABLE. If it does not, KVM will continue to await a wakeup
|
|
event in subsequent calls to KVM_RUN.
|
|
|
|
.. warning::
|
|
|
|
If userspace intends to keep the vCPU in a SUSPENDED state, it is
|
|
strongly recommended that userspace take action to suppress the
|
|
wakeup event (such as masking an interrupt). Otherwise, subsequent
|
|
calls to KVM_RUN will immediately exit with a KVM_SYSTEM_EVENT_WAKEUP
|
|
event and inadvertently waste CPU cycles.
|
|
|
|
Additionally, if userspace takes action to suppress a wakeup event,
|
|
it is strongly recommended that it also restores the vCPU to its
|
|
original state when the vCPU is made RUNNABLE again. For example,
|
|
if userspace masked a pending interrupt to suppress the wakeup,
|
|
the interrupt should be unmasked before returning control to the
|
|
guest.
|
|
|
|
For riscv:
|
|
^^^^^^^^^^
|
|
|
|
The only states that are valid are KVM_MP_STATE_STOPPED and
|
|
KVM_MP_STATE_RUNNABLE which reflect if the vcpu is paused or not.
|
|
|
|
4.39 KVM_SET_MP_STATE
|
|
---------------------
|
|
|
|
:Capability: KVM_CAP_MP_STATE
|
|
:Architectures: x86, s390, arm64, riscv
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_mp_state (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
Sets the vcpu's current "multiprocessing state"; see KVM_GET_MP_STATE for
|
|
arguments.
|
|
|
|
On x86, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an
|
|
in-kernel irqchip, the multiprocessing state must be maintained by userspace on
|
|
these architectures.
|
|
|
|
For arm64/riscv:
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
The only states that are valid are KVM_MP_STATE_STOPPED and
|
|
KVM_MP_STATE_RUNNABLE which reflect if the vcpu should be paused or not.
|
|
|
|
4.40 KVM_SET_IDENTITY_MAP_ADDR
|
|
------------------------------
|
|
|
|
:Capability: KVM_CAP_SET_IDENTITY_MAP_ADDR
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: unsigned long identity (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This ioctl defines the physical address of a one-page region in the guest
|
|
physical address space. The region must be within the first 4GB of the
|
|
guest physical address space and must not conflict with any memory slot
|
|
or any mmio address. The guest may malfunction if it accesses this memory
|
|
region.
|
|
|
|
Setting the address to 0 will result in resetting the address to its default
|
|
(0xfffbc000).
|
|
|
|
This ioctl is required on Intel-based hosts. This is needed on Intel hardware
|
|
because of a quirk in the virtualization implementation (see the internals
|
|
documentation when it pops into existence).
|
|
|
|
Fails if any VCPU has already been created.
|
|
|
|
4.41 KVM_SET_BOOT_CPU_ID
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_SET_BOOT_CPU_ID
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: unsigned long vcpu_id
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Define which vcpu is the Bootstrap Processor (BSP). Values are the same
|
|
as the vcpu id in KVM_CREATE_VCPU. If this ioctl is not called, the default
|
|
is vcpu 0. This ioctl has to be called before vcpu creation,
|
|
otherwise it will return EBUSY error.
|
|
|
|
|
|
4.42 KVM_GET_XSAVE
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_XSAVE
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xsave (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
|
|
::
|
|
|
|
struct kvm_xsave {
|
|
__u32 region[1024];
|
|
__u32 extra[0];
|
|
};
|
|
|
|
This ioctl would copy current vcpu's xsave struct to the userspace.
|
|
|
|
|
|
4.43 KVM_SET_XSAVE
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_XSAVE and KVM_CAP_XSAVE2
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xsave (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
|
|
struct kvm_xsave {
|
|
__u32 region[1024];
|
|
__u32 extra[0];
|
|
};
|
|
|
|
This ioctl would copy userspace's xsave struct to the kernel. It copies
|
|
as many bytes as are returned by KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2),
|
|
when invoked on the vm file descriptor. The size value returned by
|
|
KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will always be at least 4096.
|
|
Currently, it is only greater than 4096 if a dynamic feature has been
|
|
enabled with ``arch_prctl()``, but this may change in the future.
|
|
|
|
The offsets of the state save areas in struct kvm_xsave follow the
|
|
contents of CPUID leaf 0xD on the host.
|
|
|
|
|
|
4.44 KVM_GET_XCRS
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_XCRS
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xcrs (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_xcr {
|
|
__u32 xcr;
|
|
__u32 reserved;
|
|
__u64 value;
|
|
};
|
|
|
|
struct kvm_xcrs {
|
|
__u32 nr_xcrs;
|
|
__u32 flags;
|
|
struct kvm_xcr xcrs[KVM_MAX_XCRS];
|
|
__u64 padding[16];
|
|
};
|
|
|
|
This ioctl would copy current vcpu's xcrs to the userspace.
|
|
|
|
|
|
4.45 KVM_SET_XCRS
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_XCRS
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xcrs (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_xcr {
|
|
__u32 xcr;
|
|
__u32 reserved;
|
|
__u64 value;
|
|
};
|
|
|
|
struct kvm_xcrs {
|
|
__u32 nr_xcrs;
|
|
__u32 flags;
|
|
struct kvm_xcr xcrs[KVM_MAX_XCRS];
|
|
__u64 padding[16];
|
|
};
|
|
|
|
This ioctl would set vcpu's xcr to the value userspace specified.
|
|
|
|
|
|
4.46 KVM_GET_SUPPORTED_CPUID
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_EXT_CPUID
|
|
:Architectures: x86
|
|
:Type: system ioctl
|
|
:Parameters: struct kvm_cpuid2 (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_cpuid2 {
|
|
__u32 nent;
|
|
__u32 padding;
|
|
struct kvm_cpuid_entry2 entries[0];
|
|
};
|
|
|
|
#define KVM_CPUID_FLAG_SIGNIFCANT_INDEX BIT(0)
|
|
#define KVM_CPUID_FLAG_STATEFUL_FUNC BIT(1) /* deprecated */
|
|
#define KVM_CPUID_FLAG_STATE_READ_NEXT BIT(2) /* deprecated */
|
|
|
|
struct kvm_cpuid_entry2 {
|
|
__u32 function;
|
|
__u32 index;
|
|
__u32 flags;
|
|
__u32 eax;
|
|
__u32 ebx;
|
|
__u32 ecx;
|
|
__u32 edx;
|
|
__u32 padding[3];
|
|
};
|
|
|
|
This ioctl returns x86 cpuid features which are supported by both the
|
|
hardware and kvm in its default configuration. Userspace can use the
|
|
information returned by this ioctl to construct cpuid information (for
|
|
KVM_SET_CPUID2) that is consistent with hardware, kernel, and
|
|
userspace capabilities, and with user requirements (for example, the
|
|
user may wish to constrain cpuid to emulate older hardware, or for
|
|
feature consistency across a cluster).
|
|
|
|
Dynamically-enabled feature bits need to be requested with
|
|
``arch_prctl()`` before calling this ioctl. Feature bits that have not
|
|
been requested are excluded from the result.
|
|
|
|
Note that certain capabilities, such as KVM_CAP_X86_DISABLE_EXITS, may
|
|
expose cpuid features (e.g. MONITOR) which are not supported by kvm in
|
|
its default configuration. If userspace enables such capabilities, it
|
|
is responsible for modifying the results of this ioctl appropriately.
|
|
|
|
Userspace invokes KVM_GET_SUPPORTED_CPUID by passing a kvm_cpuid2 structure
|
|
with the 'nent' field indicating the number of entries in the variable-size
|
|
array 'entries'. If the number of entries is too low to describe the cpu
|
|
capabilities, an error (E2BIG) is returned. If the number is too high,
|
|
the 'nent' field is adjusted and an error (ENOMEM) is returned. If the
|
|
number is just right, the 'nent' field is adjusted to the number of valid
|
|
entries in the 'entries' array, which is then filled.
|
|
|
|
The entries returned are the host cpuid as returned by the cpuid instruction,
|
|
with unknown or unsupported features masked out. Some features (for example,
|
|
x2apic), may not be present in the host cpu, but are exposed by kvm if it can
|
|
emulate them efficiently. The fields in each entry are defined as follows:
|
|
|
|
function:
|
|
the eax value used to obtain the entry
|
|
|
|
index:
|
|
the ecx value used to obtain the entry (for entries that are
|
|
affected by ecx)
|
|
|
|
flags:
|
|
an OR of zero or more of the following:
|
|
|
|
KVM_CPUID_FLAG_SIGNIFCANT_INDEX:
|
|
if the index field is valid
|
|
|
|
eax, ebx, ecx, edx:
|
|
the values returned by the cpuid instruction for
|
|
this function/index combination
|
|
|
|
The TSC deadline timer feature (CPUID leaf 1, ecx[24]) is always returned
|
|
as false, since the feature depends on KVM_CREATE_IRQCHIP for local APIC
|
|
support. Instead it is reported via::
|
|
|
|
ioctl(KVM_CHECK_EXTENSION, KVM_CAP_TSC_DEADLINE_TIMER)
|
|
|
|
if that returns true and you use KVM_CREATE_IRQCHIP, or if you emulate the
|
|
feature in userspace, then you can enable the feature for KVM_SET_CPUID2.
|
|
|
|
|
|
4.47 KVM_PPC_GET_PVINFO
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_PPC_GET_PVINFO
|
|
:Architectures: ppc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_pvinfo (out)
|
|
:Returns: 0 on success, !0 on error
|
|
|
|
::
|
|
|
|
struct kvm_ppc_pvinfo {
|
|
__u32 flags;
|
|
__u32 hcall[4];
|
|
__u8 pad[108];
|
|
};
|
|
|
|
This ioctl fetches PV specific information that need to be passed to the guest
|
|
using the device tree or other means from vm context.
|
|
|
|
The hcall array defines 4 instructions that make up a hypercall.
|
|
|
|
If any additional field gets added to this structure later on, a bit for that
|
|
additional piece of information will be set in the flags bitmap.
|
|
|
|
The flags bitmap is defined as::
|
|
|
|
/* the host supports the ePAPR idle hcall
|
|
#define KVM_PPC_PVINFO_FLAGS_EV_IDLE (1<<0)
|
|
|
|
4.52 KVM_SET_GSI_ROUTING
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_IRQ_ROUTING
|
|
:Architectures: x86 s390 arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irq_routing (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the GSI routing table entries, overwriting any previously set entries.
|
|
|
|
On arm64, GSI routing has the following limitation:
|
|
|
|
- GSI routing does not apply to KVM_IRQ_LINE but only to KVM_IRQFD.
|
|
|
|
::
|
|
|
|
struct kvm_irq_routing {
|
|
__u32 nr;
|
|
__u32 flags;
|
|
struct kvm_irq_routing_entry entries[0];
|
|
};
|
|
|
|
No flags are specified so far, the corresponding field must be set to zero.
|
|
|
|
::
|
|
|
|
struct kvm_irq_routing_entry {
|
|
__u32 gsi;
|
|
__u32 type;
|
|
__u32 flags;
|
|
__u32 pad;
|
|
union {
|
|
struct kvm_irq_routing_irqchip irqchip;
|
|
struct kvm_irq_routing_msi msi;
|
|
struct kvm_irq_routing_s390_adapter adapter;
|
|
struct kvm_irq_routing_hv_sint hv_sint;
|
|
struct kvm_irq_routing_xen_evtchn xen_evtchn;
|
|
__u32 pad[8];
|
|
} u;
|
|
};
|
|
|
|
/* gsi routing entry types */
|
|
#define KVM_IRQ_ROUTING_IRQCHIP 1
|
|
#define KVM_IRQ_ROUTING_MSI 2
|
|
#define KVM_IRQ_ROUTING_S390_ADAPTER 3
|
|
#define KVM_IRQ_ROUTING_HV_SINT 4
|
|
#define KVM_IRQ_ROUTING_XEN_EVTCHN 5
|
|
|
|
flags:
|
|
|
|
- KVM_MSI_VALID_DEVID: used along with KVM_IRQ_ROUTING_MSI routing entry
|
|
type, specifies that the devid field contains a valid value. The per-VM
|
|
KVM_CAP_MSI_DEVID capability advertises the requirement to provide
|
|
the device ID. If this capability is not available, userspace should
|
|
never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail.
|
|
- zero otherwise
|
|
|
|
::
|
|
|
|
struct kvm_irq_routing_irqchip {
|
|
__u32 irqchip;
|
|
__u32 pin;
|
|
};
|
|
|
|
struct kvm_irq_routing_msi {
|
|
__u32 address_lo;
|
|
__u32 address_hi;
|
|
__u32 data;
|
|
union {
|
|
__u32 pad;
|
|
__u32 devid;
|
|
};
|
|
};
|
|
|
|
If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier
|
|
for the device that wrote the MSI message. For PCI, this is usually a
|
|
BFD identifier in the lower 16 bits.
|
|
|
|
On x86, address_hi is ignored unless the KVM_X2APIC_API_USE_32BIT_IDS
|
|
feature of KVM_CAP_X2APIC_API capability is enabled. If it is enabled,
|
|
address_hi bits 31-8 provide bits 31-8 of the destination id. Bits 7-0 of
|
|
address_hi must be zero.
|
|
|
|
::
|
|
|
|
struct kvm_irq_routing_s390_adapter {
|
|
__u64 ind_addr;
|
|
__u64 summary_addr;
|
|
__u64 ind_offset;
|
|
__u32 summary_offset;
|
|
__u32 adapter_id;
|
|
};
|
|
|
|
struct kvm_irq_routing_hv_sint {
|
|
__u32 vcpu;
|
|
__u32 sint;
|
|
};
|
|
|
|
struct kvm_irq_routing_xen_evtchn {
|
|
__u32 port;
|
|
__u32 vcpu;
|
|
__u32 priority;
|
|
};
|
|
|
|
|
|
When KVM_CAP_XEN_HVM includes the KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL bit
|
|
in its indication of supported features, routing to Xen event channels
|
|
is supported. Although the priority field is present, only the value
|
|
KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL is supported, which means delivery by
|
|
2 level event channels. FIFO event channel support may be added in
|
|
the future.
|
|
|
|
|
|
4.55 KVM_SET_TSC_KHZ
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_TSC_CONTROL / KVM_CAP_VM_TSC_CONTROL
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl / vm ioctl
|
|
:Parameters: virtual tsc_khz
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Specifies the tsc frequency for the virtual machine. The unit of the
|
|
frequency is KHz.
|
|
|
|
If the KVM_CAP_VM_TSC_CONTROL capability is advertised, this can also
|
|
be used as a vm ioctl to set the initial tsc frequency of subsequently
|
|
created vCPUs.
|
|
|
|
4.56 KVM_GET_TSC_KHZ
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_GET_TSC_KHZ / KVM_CAP_VM_TSC_CONTROL
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl / vm ioctl
|
|
:Parameters: none
|
|
:Returns: virtual tsc-khz on success, negative value on error
|
|
|
|
Returns the tsc frequency of the guest. The unit of the return value is
|
|
KHz. If the host has unstable tsc this ioctl returns -EIO instead as an
|
|
error.
|
|
|
|
|
|
4.57 KVM_GET_LAPIC
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_lapic_state (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
#define KVM_APIC_REG_SIZE 0x400
|
|
struct kvm_lapic_state {
|
|
char regs[KVM_APIC_REG_SIZE];
|
|
};
|
|
|
|
Reads the Local APIC registers and copies them into the input argument. The
|
|
data format and layout are the same as documented in the architecture manual.
|
|
|
|
If KVM_X2APIC_API_USE_32BIT_IDS feature of KVM_CAP_X2APIC_API is
|
|
enabled, then the format of APIC_ID register depends on the APIC mode
|
|
(reported by MSR_IA32_APICBASE) of its VCPU. x2APIC stores APIC ID in
|
|
the APIC_ID register (bytes 32-35). xAPIC only allows an 8-bit APIC ID
|
|
which is stored in bits 31-24 of the APIC register, or equivalently in
|
|
byte 35 of struct kvm_lapic_state's regs field. KVM_GET_LAPIC must then
|
|
be called after MSR_IA32_APICBASE has been set with KVM_SET_MSR.
|
|
|
|
If KVM_X2APIC_API_USE_32BIT_IDS feature is disabled, struct kvm_lapic_state
|
|
always uses xAPIC format.
|
|
|
|
|
|
4.58 KVM_SET_LAPIC
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_IRQCHIP
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_lapic_state (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
#define KVM_APIC_REG_SIZE 0x400
|
|
struct kvm_lapic_state {
|
|
char regs[KVM_APIC_REG_SIZE];
|
|
};
|
|
|
|
Copies the input argument into the Local APIC registers. The data format
|
|
and layout are the same as documented in the architecture manual.
|
|
|
|
The format of the APIC ID register (bytes 32-35 of struct kvm_lapic_state's
|
|
regs field) depends on the state of the KVM_CAP_X2APIC_API capability.
|
|
See the note in KVM_GET_LAPIC.
|
|
|
|
|
|
4.59 KVM_IOEVENTFD
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_IOEVENTFD
|
|
:Architectures: all
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ioeventfd (in)
|
|
:Returns: 0 on success, !0 on error
|
|
|
|
This ioctl attaches or detaches an ioeventfd to a legal pio/mmio address
|
|
within the guest. A guest write in the registered address will signal the
|
|
provided event instead of triggering an exit.
|
|
|
|
::
|
|
|
|
struct kvm_ioeventfd {
|
|
__u64 datamatch;
|
|
__u64 addr; /* legal pio/mmio address */
|
|
__u32 len; /* 0, 1, 2, 4, or 8 bytes */
|
|
__s32 fd;
|
|
__u32 flags;
|
|
__u8 pad[36];
|
|
};
|
|
|
|
For the special case of virtio-ccw devices on s390, the ioevent is matched
|
|
to a subchannel/virtqueue tuple instead.
|
|
|
|
The following flags are defined::
|
|
|
|
#define KVM_IOEVENTFD_FLAG_DATAMATCH (1 << kvm_ioeventfd_flag_nr_datamatch)
|
|
#define KVM_IOEVENTFD_FLAG_PIO (1 << kvm_ioeventfd_flag_nr_pio)
|
|
#define KVM_IOEVENTFD_FLAG_DEASSIGN (1 << kvm_ioeventfd_flag_nr_deassign)
|
|
#define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY \
|
|
(1 << kvm_ioeventfd_flag_nr_virtio_ccw_notify)
|
|
|
|
If datamatch flag is set, the event will be signaled only if the written value
|
|
to the registered address is equal to datamatch in struct kvm_ioeventfd.
|
|
|
|
For virtio-ccw devices, addr contains the subchannel id and datamatch the
|
|
virtqueue index.
|
|
|
|
With KVM_CAP_IOEVENTFD_ANY_LENGTH, a zero length ioeventfd is allowed, and
|
|
the kernel will ignore the length of guest write and may get a faster vmexit.
|
|
The speedup may only apply to specific architectures, but the ioeventfd will
|
|
work anyway.
|
|
|
|
4.60 KVM_DIRTY_TLB
|
|
------------------
|
|
|
|
:Capability: KVM_CAP_SW_TLB
|
|
:Architectures: ppc
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_dirty_tlb (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_dirty_tlb {
|
|
__u64 bitmap;
|
|
__u32 num_dirty;
|
|
};
|
|
|
|
This must be called whenever userspace has changed an entry in the shared
|
|
TLB, prior to calling KVM_RUN on the associated vcpu.
|
|
|
|
The "bitmap" field is the userspace address of an array. This array
|
|
consists of a number of bits, equal to the total number of TLB entries as
|
|
determined by the last successful call to KVM_CONFIG_TLB, rounded up to the
|
|
nearest multiple of 64.
|
|
|
|
Each bit corresponds to one TLB entry, ordered the same as in the shared TLB
|
|
array.
|
|
|
|
The array is little-endian: the bit 0 is the least significant bit of the
|
|
first byte, bit 8 is the least significant bit of the second byte, etc.
|
|
This avoids any complications with differing word sizes.
|
|
|
|
The "num_dirty" field is a performance hint for KVM to determine whether it
|
|
should skip processing the bitmap and just invalidate everything. It must
|
|
be set to the number of set bits in the bitmap.
|
|
|
|
|
|
4.62 KVM_CREATE_SPAPR_TCE
|
|
-------------------------
|
|
|
|
:Capability: KVM_CAP_SPAPR_TCE
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_create_spapr_tce (in)
|
|
:Returns: file descriptor for manipulating the created TCE table
|
|
|
|
This creates a virtual TCE (translation control entry) table, which
|
|
is an IOMMU for PAPR-style virtual I/O. It is used to translate
|
|
logical addresses used in virtual I/O into guest physical addresses,
|
|
and provides a scatter/gather capability for PAPR virtual I/O.
|
|
|
|
::
|
|
|
|
/* for KVM_CAP_SPAPR_TCE */
|
|
struct kvm_create_spapr_tce {
|
|
__u64 liobn;
|
|
__u32 window_size;
|
|
};
|
|
|
|
The liobn field gives the logical IO bus number for which to create a
|
|
TCE table. The window_size field specifies the size of the DMA window
|
|
which this TCE table will translate - the table will contain one 64
|
|
bit TCE entry for every 4kiB of the DMA window.
|
|
|
|
When the guest issues an H_PUT_TCE hcall on a liobn for which a TCE
|
|
table has been created using this ioctl(), the kernel will handle it
|
|
in real mode, updating the TCE table. H_PUT_TCE calls for other
|
|
liobns will cause a vm exit and must be handled by userspace.
|
|
|
|
The return value is a file descriptor which can be passed to mmap(2)
|
|
to map the created TCE table into userspace. This lets userspace read
|
|
the entries written by kernel-handled H_PUT_TCE calls, and also lets
|
|
userspace update the TCE table directly which is useful in some
|
|
circumstances.
|
|
|
|
|
|
4.63 KVM_ALLOCATE_RMA
|
|
---------------------
|
|
|
|
:Capability: KVM_CAP_PPC_RMA
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_allocate_rma (out)
|
|
:Returns: file descriptor for mapping the allocated RMA
|
|
|
|
This allocates a Real Mode Area (RMA) from the pool allocated at boot
|
|
time by the kernel. An RMA is a physically-contiguous, aligned region
|
|
of memory used on older POWER processors to provide the memory which
|
|
will be accessed by real-mode (MMU off) accesses in a KVM guest.
|
|
POWER processors support a set of sizes for the RMA that usually
|
|
includes 64MB, 128MB, 256MB and some larger powers of two.
|
|
|
|
::
|
|
|
|
/* for KVM_ALLOCATE_RMA */
|
|
struct kvm_allocate_rma {
|
|
__u64 rma_size;
|
|
};
|
|
|
|
The return value is a file descriptor which can be passed to mmap(2)
|
|
to map the allocated RMA into userspace. The mapped area can then be
|
|
passed to the KVM_SET_USER_MEMORY_REGION ioctl to establish it as the
|
|
RMA for a virtual machine. The size of the RMA in bytes (which is
|
|
fixed at host kernel boot time) is returned in the rma_size field of
|
|
the argument structure.
|
|
|
|
The KVM_CAP_PPC_RMA capability is 1 or 2 if the KVM_ALLOCATE_RMA ioctl
|
|
is supported; 2 if the processor requires all virtual machines to have
|
|
an RMA, or 1 if the processor can use an RMA but doesn't require it,
|
|
because it supports the Virtual RMA (VRMA) facility.
|
|
|
|
|
|
4.64 KVM_NMI
|
|
------------
|
|
|
|
:Capability: KVM_CAP_USER_NMI
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Queues an NMI on the thread's vcpu. Note this is well defined only
|
|
when KVM_CREATE_IRQCHIP has not been called, since this is an interface
|
|
between the virtual cpu core and virtual local APIC. After KVM_CREATE_IRQCHIP
|
|
has been called, this interface is completely emulated within the kernel.
|
|
|
|
To use this to emulate the LINT1 input with KVM_CREATE_IRQCHIP, use the
|
|
following algorithm:
|
|
|
|
- pause the vcpu
|
|
- read the local APIC's state (KVM_GET_LAPIC)
|
|
- check whether changing LINT1 will queue an NMI (see the LVT entry for LINT1)
|
|
- if so, issue KVM_NMI
|
|
- resume the vcpu
|
|
|
|
Some guests configure the LINT1 NMI input to cause a panic, aiding in
|
|
debugging.
|
|
|
|
|
|
4.65 KVM_S390_UCAS_MAP
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_S390_UCONTROL
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_s390_ucas_mapping (in)
|
|
:Returns: 0 in case of success
|
|
|
|
The parameter is defined like this::
|
|
|
|
struct kvm_s390_ucas_mapping {
|
|
__u64 user_addr;
|
|
__u64 vcpu_addr;
|
|
__u64 length;
|
|
};
|
|
|
|
This ioctl maps the memory at "user_addr" with the length "length" to
|
|
the vcpu's address space starting at "vcpu_addr". All parameters need to
|
|
be aligned by 1 megabyte.
|
|
|
|
|
|
4.66 KVM_S390_UCAS_UNMAP
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_S390_UCONTROL
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_s390_ucas_mapping (in)
|
|
:Returns: 0 in case of success
|
|
|
|
The parameter is defined like this::
|
|
|
|
struct kvm_s390_ucas_mapping {
|
|
__u64 user_addr;
|
|
__u64 vcpu_addr;
|
|
__u64 length;
|
|
};
|
|
|
|
This ioctl unmaps the memory in the vcpu's address space starting at
|
|
"vcpu_addr" with the length "length". The field "user_addr" is ignored.
|
|
All parameters need to be aligned by 1 megabyte.
|
|
|
|
|
|
4.67 KVM_S390_VCPU_FAULT
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_S390_UCONTROL
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: vcpu absolute address (in)
|
|
:Returns: 0 in case of success
|
|
|
|
This call creates a page table entry on the virtual cpu's address space
|
|
(for user controlled virtual machines) or the virtual machine's address
|
|
space (for regular virtual machines). This only works for minor faults,
|
|
thus it's recommended to access subject memory page via the user page
|
|
table upfront. This is useful to handle validity intercepts for user
|
|
controlled virtual machines to fault in the virtual cpu's lowcore pages
|
|
prior to calling the KVM_RUN ioctl.
|
|
|
|
|
|
4.68 KVM_SET_ONE_REG
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_ONE_REG
|
|
:Architectures: all
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_one_reg (in)
|
|
:Returns: 0 on success, negative value on failure
|
|
|
|
Errors:
|
|
|
|
====== ============================================================
|
|
ENOENT no such register
|
|
EINVAL invalid register ID, or no such register or used with VMs in
|
|
protected virtualization mode on s390
|
|
EPERM (arm64) register access not allowed before vcpu finalization
|
|
====== ============================================================
|
|
|
|
(These error codes are indicative only: do not rely on a specific error
|
|
code being returned in a specific situation.)
|
|
|
|
::
|
|
|
|
struct kvm_one_reg {
|
|
__u64 id;
|
|
__u64 addr;
|
|
};
|
|
|
|
Using this ioctl, a single vcpu register can be set to a specific value
|
|
defined by user space with the passed in struct kvm_one_reg, where id
|
|
refers to the register identifier as described below and addr is a pointer
|
|
to a variable with the respective size. There can be architecture agnostic
|
|
and architecture specific registers. Each have their own range of operation
|
|
and their own constants and width. To keep track of the implemented
|
|
registers, find a list below:
|
|
|
|
======= =============================== ============
|
|
Arch Register Width (bits)
|
|
======= =============================== ============
|
|
PPC KVM_REG_PPC_HIOR 64
|
|
PPC KVM_REG_PPC_IAC1 64
|
|
PPC KVM_REG_PPC_IAC2 64
|
|
PPC KVM_REG_PPC_IAC3 64
|
|
PPC KVM_REG_PPC_IAC4 64
|
|
PPC KVM_REG_PPC_DAC1 64
|
|
PPC KVM_REG_PPC_DAC2 64
|
|
PPC KVM_REG_PPC_DABR 64
|
|
PPC KVM_REG_PPC_DSCR 64
|
|
PPC KVM_REG_PPC_PURR 64
|
|
PPC KVM_REG_PPC_SPURR 64
|
|
PPC KVM_REG_PPC_DAR 64
|
|
PPC KVM_REG_PPC_DSISR 32
|
|
PPC KVM_REG_PPC_AMR 64
|
|
PPC KVM_REG_PPC_UAMOR 64
|
|
PPC KVM_REG_PPC_MMCR0 64
|
|
PPC KVM_REG_PPC_MMCR1 64
|
|
PPC KVM_REG_PPC_MMCRA 64
|
|
PPC KVM_REG_PPC_MMCR2 64
|
|
PPC KVM_REG_PPC_MMCRS 64
|
|
PPC KVM_REG_PPC_MMCR3 64
|
|
PPC KVM_REG_PPC_SIAR 64
|
|
PPC KVM_REG_PPC_SDAR 64
|
|
PPC KVM_REG_PPC_SIER 64
|
|
PPC KVM_REG_PPC_SIER2 64
|
|
PPC KVM_REG_PPC_SIER3 64
|
|
PPC KVM_REG_PPC_PMC1 32
|
|
PPC KVM_REG_PPC_PMC2 32
|
|
PPC KVM_REG_PPC_PMC3 32
|
|
PPC KVM_REG_PPC_PMC4 32
|
|
PPC KVM_REG_PPC_PMC5 32
|
|
PPC KVM_REG_PPC_PMC6 32
|
|
PPC KVM_REG_PPC_PMC7 32
|
|
PPC KVM_REG_PPC_PMC8 32
|
|
PPC KVM_REG_PPC_FPR0 64
|
|
...
|
|
PPC KVM_REG_PPC_FPR31 64
|
|
PPC KVM_REG_PPC_VR0 128
|
|
...
|
|
PPC KVM_REG_PPC_VR31 128
|
|
PPC KVM_REG_PPC_VSR0 128
|
|
...
|
|
PPC KVM_REG_PPC_VSR31 128
|
|
PPC KVM_REG_PPC_FPSCR 64
|
|
PPC KVM_REG_PPC_VSCR 32
|
|
PPC KVM_REG_PPC_VPA_ADDR 64
|
|
PPC KVM_REG_PPC_VPA_SLB 128
|
|
PPC KVM_REG_PPC_VPA_DTL 128
|
|
PPC KVM_REG_PPC_EPCR 32
|
|
PPC KVM_REG_PPC_EPR 32
|
|
PPC KVM_REG_PPC_TCR 32
|
|
PPC KVM_REG_PPC_TSR 32
|
|
PPC KVM_REG_PPC_OR_TSR 32
|
|
PPC KVM_REG_PPC_CLEAR_TSR 32
|
|
PPC KVM_REG_PPC_MAS0 32
|
|
PPC KVM_REG_PPC_MAS1 32
|
|
PPC KVM_REG_PPC_MAS2 64
|
|
PPC KVM_REG_PPC_MAS7_3 64
|
|
PPC KVM_REG_PPC_MAS4 32
|
|
PPC KVM_REG_PPC_MAS6 32
|
|
PPC KVM_REG_PPC_MMUCFG 32
|
|
PPC KVM_REG_PPC_TLB0CFG 32
|
|
PPC KVM_REG_PPC_TLB1CFG 32
|
|
PPC KVM_REG_PPC_TLB2CFG 32
|
|
PPC KVM_REG_PPC_TLB3CFG 32
|
|
PPC KVM_REG_PPC_TLB0PS 32
|
|
PPC KVM_REG_PPC_TLB1PS 32
|
|
PPC KVM_REG_PPC_TLB2PS 32
|
|
PPC KVM_REG_PPC_TLB3PS 32
|
|
PPC KVM_REG_PPC_EPTCFG 32
|
|
PPC KVM_REG_PPC_ICP_STATE 64
|
|
PPC KVM_REG_PPC_VP_STATE 128
|
|
PPC KVM_REG_PPC_TB_OFFSET 64
|
|
PPC KVM_REG_PPC_SPMC1 32
|
|
PPC KVM_REG_PPC_SPMC2 32
|
|
PPC KVM_REG_PPC_IAMR 64
|
|
PPC KVM_REG_PPC_TFHAR 64
|
|
PPC KVM_REG_PPC_TFIAR 64
|
|
PPC KVM_REG_PPC_TEXASR 64
|
|
PPC KVM_REG_PPC_FSCR 64
|
|
PPC KVM_REG_PPC_PSPB 32
|
|
PPC KVM_REG_PPC_EBBHR 64
|
|
PPC KVM_REG_PPC_EBBRR 64
|
|
PPC KVM_REG_PPC_BESCR 64
|
|
PPC KVM_REG_PPC_TAR 64
|
|
PPC KVM_REG_PPC_DPDES 64
|
|
PPC KVM_REG_PPC_DAWR 64
|
|
PPC KVM_REG_PPC_DAWRX 64
|
|
PPC KVM_REG_PPC_CIABR 64
|
|
PPC KVM_REG_PPC_IC 64
|
|
PPC KVM_REG_PPC_VTB 64
|
|
PPC KVM_REG_PPC_CSIGR 64
|
|
PPC KVM_REG_PPC_TACR 64
|
|
PPC KVM_REG_PPC_TCSCR 64
|
|
PPC KVM_REG_PPC_PID 64
|
|
PPC KVM_REG_PPC_ACOP 64
|
|
PPC KVM_REG_PPC_VRSAVE 32
|
|
PPC KVM_REG_PPC_LPCR 32
|
|
PPC KVM_REG_PPC_LPCR_64 64
|
|
PPC KVM_REG_PPC_PPR 64
|
|
PPC KVM_REG_PPC_ARCH_COMPAT 32
|
|
PPC KVM_REG_PPC_DABRX 32
|
|
PPC KVM_REG_PPC_WORT 64
|
|
PPC KVM_REG_PPC_SPRG9 64
|
|
PPC KVM_REG_PPC_DBSR 32
|
|
PPC KVM_REG_PPC_TIDR 64
|
|
PPC KVM_REG_PPC_PSSCR 64
|
|
PPC KVM_REG_PPC_DEC_EXPIRY 64
|
|
PPC KVM_REG_PPC_PTCR 64
|
|
PPC KVM_REG_PPC_DAWR1 64
|
|
PPC KVM_REG_PPC_DAWRX1 64
|
|
PPC KVM_REG_PPC_TM_GPR0 64
|
|
...
|
|
PPC KVM_REG_PPC_TM_GPR31 64
|
|
PPC KVM_REG_PPC_TM_VSR0 128
|
|
...
|
|
PPC KVM_REG_PPC_TM_VSR63 128
|
|
PPC KVM_REG_PPC_TM_CR 64
|
|
PPC KVM_REG_PPC_TM_LR 64
|
|
PPC KVM_REG_PPC_TM_CTR 64
|
|
PPC KVM_REG_PPC_TM_FPSCR 64
|
|
PPC KVM_REG_PPC_TM_AMR 64
|
|
PPC KVM_REG_PPC_TM_PPR 64
|
|
PPC KVM_REG_PPC_TM_VRSAVE 64
|
|
PPC KVM_REG_PPC_TM_VSCR 32
|
|
PPC KVM_REG_PPC_TM_DSCR 64
|
|
PPC KVM_REG_PPC_TM_TAR 64
|
|
PPC KVM_REG_PPC_TM_XER 64
|
|
|
|
MIPS KVM_REG_MIPS_R0 64
|
|
...
|
|
MIPS KVM_REG_MIPS_R31 64
|
|
MIPS KVM_REG_MIPS_HI 64
|
|
MIPS KVM_REG_MIPS_LO 64
|
|
MIPS KVM_REG_MIPS_PC 64
|
|
MIPS KVM_REG_MIPS_CP0_INDEX 32
|
|
MIPS KVM_REG_MIPS_CP0_ENTRYLO0 64
|
|
MIPS KVM_REG_MIPS_CP0_ENTRYLO1 64
|
|
MIPS KVM_REG_MIPS_CP0_CONTEXT 64
|
|
MIPS KVM_REG_MIPS_CP0_CONTEXTCONFIG 32
|
|
MIPS KVM_REG_MIPS_CP0_USERLOCAL 64
|
|
MIPS KVM_REG_MIPS_CP0_XCONTEXTCONFIG 64
|
|
MIPS KVM_REG_MIPS_CP0_PAGEMASK 32
|
|
MIPS KVM_REG_MIPS_CP0_PAGEGRAIN 32
|
|
MIPS KVM_REG_MIPS_CP0_SEGCTL0 64
|
|
MIPS KVM_REG_MIPS_CP0_SEGCTL1 64
|
|
MIPS KVM_REG_MIPS_CP0_SEGCTL2 64
|
|
MIPS KVM_REG_MIPS_CP0_PWBASE 64
|
|
MIPS KVM_REG_MIPS_CP0_PWFIELD 64
|
|
MIPS KVM_REG_MIPS_CP0_PWSIZE 64
|
|
MIPS KVM_REG_MIPS_CP0_WIRED 32
|
|
MIPS KVM_REG_MIPS_CP0_PWCTL 32
|
|
MIPS KVM_REG_MIPS_CP0_HWRENA 32
|
|
MIPS KVM_REG_MIPS_CP0_BADVADDR 64
|
|
MIPS KVM_REG_MIPS_CP0_BADINSTR 32
|
|
MIPS KVM_REG_MIPS_CP0_BADINSTRP 32
|
|
MIPS KVM_REG_MIPS_CP0_COUNT 32
|
|
MIPS KVM_REG_MIPS_CP0_ENTRYHI 64
|
|
MIPS KVM_REG_MIPS_CP0_COMPARE 32
|
|
MIPS KVM_REG_MIPS_CP0_STATUS 32
|
|
MIPS KVM_REG_MIPS_CP0_INTCTL 32
|
|
MIPS KVM_REG_MIPS_CP0_CAUSE 32
|
|
MIPS KVM_REG_MIPS_CP0_EPC 64
|
|
MIPS KVM_REG_MIPS_CP0_PRID 32
|
|
MIPS KVM_REG_MIPS_CP0_EBASE 64
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG1 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG2 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG3 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG4 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG5 32
|
|
MIPS KVM_REG_MIPS_CP0_CONFIG7 32
|
|
MIPS KVM_REG_MIPS_CP0_XCONTEXT 64
|
|
MIPS KVM_REG_MIPS_CP0_ERROREPC 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH1 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH2 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH3 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH4 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH5 64
|
|
MIPS KVM_REG_MIPS_CP0_KSCRATCH6 64
|
|
MIPS KVM_REG_MIPS_CP0_MAAR(0..63) 64
|
|
MIPS KVM_REG_MIPS_COUNT_CTL 64
|
|
MIPS KVM_REG_MIPS_COUNT_RESUME 64
|
|
MIPS KVM_REG_MIPS_COUNT_HZ 64
|
|
MIPS KVM_REG_MIPS_FPR_32(0..31) 32
|
|
MIPS KVM_REG_MIPS_FPR_64(0..31) 64
|
|
MIPS KVM_REG_MIPS_VEC_128(0..31) 128
|
|
MIPS KVM_REG_MIPS_FCR_IR 32
|
|
MIPS KVM_REG_MIPS_FCR_CSR 32
|
|
MIPS KVM_REG_MIPS_MSA_IR 32
|
|
MIPS KVM_REG_MIPS_MSA_CSR 32
|
|
======= =============================== ============
|
|
|
|
ARM registers are mapped using the lower 32 bits. The upper 16 of that
|
|
is the register group type, or coprocessor number:
|
|
|
|
ARM core registers have the following id bit patterns::
|
|
|
|
0x4020 0000 0010 <index into the kvm_regs struct:16>
|
|
|
|
ARM 32-bit CP15 registers have the following id bit patterns::
|
|
|
|
0x4020 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>
|
|
|
|
ARM 64-bit CP15 registers have the following id bit patterns::
|
|
|
|
0x4030 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
|
|
|
|
ARM CCSIDR registers are demultiplexed by CSSELR value::
|
|
|
|
0x4020 0000 0011 00 <csselr:8>
|
|
|
|
ARM 32-bit VFP control registers have the following id bit patterns::
|
|
|
|
0x4020 0000 0012 1 <regno:12>
|
|
|
|
ARM 64-bit FP registers have the following id bit patterns::
|
|
|
|
0x4030 0000 0012 0 <regno:12>
|
|
|
|
ARM firmware pseudo-registers have the following bit pattern::
|
|
|
|
0x4030 0000 0014 <regno:16>
|
|
|
|
|
|
arm64 registers are mapped using the lower 32 bits. The upper 16 of
|
|
that is the register group type, or coprocessor number:
|
|
|
|
arm64 core/FP-SIMD registers have the following id bit patterns. Note
|
|
that the size of the access is variable, as the kvm_regs structure
|
|
contains elements ranging from 32 to 128 bits. The index is a 32bit
|
|
value in the kvm_regs structure seen as a 32bit array::
|
|
|
|
0x60x0 0000 0010 <index into the kvm_regs struct:16>
|
|
|
|
Specifically:
|
|
|
|
======================= ========= ===== =======================================
|
|
Encoding Register Bits kvm_regs member
|
|
======================= ========= ===== =======================================
|
|
0x6030 0000 0010 0000 X0 64 regs.regs[0]
|
|
0x6030 0000 0010 0002 X1 64 regs.regs[1]
|
|
...
|
|
0x6030 0000 0010 003c X30 64 regs.regs[30]
|
|
0x6030 0000 0010 003e SP 64 regs.sp
|
|
0x6030 0000 0010 0040 PC 64 regs.pc
|
|
0x6030 0000 0010 0042 PSTATE 64 regs.pstate
|
|
0x6030 0000 0010 0044 SP_EL1 64 sp_el1
|
|
0x6030 0000 0010 0046 ELR_EL1 64 elr_el1
|
|
0x6030 0000 0010 0048 SPSR_EL1 64 spsr[KVM_SPSR_EL1] (alias SPSR_SVC)
|
|
0x6030 0000 0010 004a SPSR_ABT 64 spsr[KVM_SPSR_ABT]
|
|
0x6030 0000 0010 004c SPSR_UND 64 spsr[KVM_SPSR_UND]
|
|
0x6030 0000 0010 004e SPSR_IRQ 64 spsr[KVM_SPSR_IRQ]
|
|
0x6060 0000 0010 0050 SPSR_FIQ 64 spsr[KVM_SPSR_FIQ]
|
|
0x6040 0000 0010 0054 V0 128 fp_regs.vregs[0] [1]_
|
|
0x6040 0000 0010 0058 V1 128 fp_regs.vregs[1] [1]_
|
|
...
|
|
0x6040 0000 0010 00d0 V31 128 fp_regs.vregs[31] [1]_
|
|
0x6020 0000 0010 00d4 FPSR 32 fp_regs.fpsr
|
|
0x6020 0000 0010 00d5 FPCR 32 fp_regs.fpcr
|
|
======================= ========= ===== =======================================
|
|
|
|
.. [1] These encodings are not accepted for SVE-enabled vcpus. See
|
|
KVM_ARM_VCPU_INIT.
|
|
|
|
The equivalent register content can be accessed via bits [127:0] of
|
|
the corresponding SVE Zn registers instead for vcpus that have SVE
|
|
enabled (see below).
|
|
|
|
arm64 CCSIDR registers are demultiplexed by CSSELR value::
|
|
|
|
0x6020 0000 0011 00 <csselr:8>
|
|
|
|
arm64 system registers have the following id bit patterns::
|
|
|
|
0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3>
|
|
|
|
.. warning::
|
|
|
|
Two system register IDs do not follow the specified pattern. These
|
|
are KVM_REG_ARM_TIMER_CVAL and KVM_REG_ARM_TIMER_CNT, which map to
|
|
system registers CNTV_CVAL_EL0 and CNTVCT_EL0 respectively. These
|
|
two had their values accidentally swapped, which means TIMER_CVAL is
|
|
derived from the register encoding for CNTVCT_EL0 and TIMER_CNT is
|
|
derived from the register encoding for CNTV_CVAL_EL0. As this is
|
|
API, it must remain this way.
|
|
|
|
arm64 firmware pseudo-registers have the following bit pattern::
|
|
|
|
0x6030 0000 0014 <regno:16>
|
|
|
|
arm64 SVE registers have the following bit patterns::
|
|
|
|
0x6080 0000 0015 00 <n:5> <slice:5> Zn bits[2048*slice + 2047 : 2048*slice]
|
|
0x6050 0000 0015 04 <n:4> <slice:5> Pn bits[256*slice + 255 : 256*slice]
|
|
0x6050 0000 0015 060 <slice:5> FFR bits[256*slice + 255 : 256*slice]
|
|
0x6060 0000 0015 ffff KVM_REG_ARM64_SVE_VLS pseudo-register
|
|
|
|
Access to register IDs where 2048 * slice >= 128 * max_vq will fail with
|
|
ENOENT. max_vq is the vcpu's maximum supported vector length in 128-bit
|
|
quadwords: see [2]_ below.
|
|
|
|
These registers are only accessible on vcpus for which SVE is enabled.
|
|
See KVM_ARM_VCPU_INIT for details.
|
|
|
|
In addition, except for KVM_REG_ARM64_SVE_VLS, these registers are not
|
|
accessible until the vcpu's SVE configuration has been finalized
|
|
using KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE). See KVM_ARM_VCPU_INIT
|
|
and KVM_ARM_VCPU_FINALIZE for more information about this procedure.
|
|
|
|
KVM_REG_ARM64_SVE_VLS is a pseudo-register that allows the set of vector
|
|
lengths supported by the vcpu to be discovered and configured by
|
|
userspace. When transferred to or from user memory via KVM_GET_ONE_REG
|
|
or KVM_SET_ONE_REG, the value of this register is of type
|
|
__u64[KVM_ARM64_SVE_VLS_WORDS], and encodes the set of vector lengths as
|
|
follows::
|
|
|
|
__u64 vector_lengths[KVM_ARM64_SVE_VLS_WORDS];
|
|
|
|
if (vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX &&
|
|
((vector_lengths[(vq - KVM_ARM64_SVE_VQ_MIN) / 64] >>
|
|
((vq - KVM_ARM64_SVE_VQ_MIN) % 64)) & 1))
|
|
/* Vector length vq * 16 bytes supported */
|
|
else
|
|
/* Vector length vq * 16 bytes not supported */
|
|
|
|
.. [2] The maximum value vq for which the above condition is true is
|
|
max_vq. This is the maximum vector length available to the guest on
|
|
this vcpu, and determines which register slices are visible through
|
|
this ioctl interface.
|
|
|
|
(See Documentation/arm64/sve.rst for an explanation of the "vq"
|
|
nomenclature.)
|
|
|
|
KVM_REG_ARM64_SVE_VLS is only accessible after KVM_ARM_VCPU_INIT.
|
|
KVM_ARM_VCPU_INIT initialises it to the best set of vector lengths that
|
|
the host supports.
|
|
|
|
Userspace may subsequently modify it if desired until the vcpu's SVE
|
|
configuration is finalized using KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE).
|
|
|
|
Apart from simply removing all vector lengths from the host set that
|
|
exceed some value, support for arbitrarily chosen sets of vector lengths
|
|
is hardware-dependent and may not be available. Attempting to configure
|
|
an invalid set of vector lengths via KVM_SET_ONE_REG will fail with
|
|
EINVAL.
|
|
|
|
After the vcpu's SVE configuration is finalized, further attempts to
|
|
write this register will fail with EPERM.
|
|
|
|
arm64 bitmap feature firmware pseudo-registers have the following bit pattern::
|
|
|
|
0x6030 0000 0016 <regno:16>
|
|
|
|
The bitmap feature firmware registers exposes the hypercall services that
|
|
are available for userspace to configure. The set bits corresponds to the
|
|
services that are available for the guests to access. By default, KVM
|
|
sets all the supported bits during VM initialization. The userspace can
|
|
discover the available services via KVM_GET_ONE_REG, and write back the
|
|
bitmap corresponding to the features that it wishes guests to see via
|
|
KVM_SET_ONE_REG.
|
|
|
|
Note: These registers are immutable once any of the vCPUs of the VM has
|
|
run at least once. A KVM_SET_ONE_REG in such a scenario will return
|
|
a -EBUSY to userspace.
|
|
|
|
(See Documentation/virt/kvm/arm/hypercalls.rst for more details.)
|
|
|
|
|
|
MIPS registers are mapped using the lower 32 bits. The upper 16 of that is
|
|
the register group type:
|
|
|
|
MIPS core registers (see above) have the following id bit patterns::
|
|
|
|
0x7030 0000 0000 <reg:16>
|
|
|
|
MIPS CP0 registers (see KVM_REG_MIPS_CP0_* above) have the following id bit
|
|
patterns depending on whether they're 32-bit or 64-bit registers::
|
|
|
|
0x7020 0000 0001 00 <reg:5> <sel:3> (32-bit)
|
|
0x7030 0000 0001 00 <reg:5> <sel:3> (64-bit)
|
|
|
|
Note: KVM_REG_MIPS_CP0_ENTRYLO0 and KVM_REG_MIPS_CP0_ENTRYLO1 are the MIPS64
|
|
versions of the EntryLo registers regardless of the word size of the host
|
|
hardware, host kernel, guest, and whether XPA is present in the guest, i.e.
|
|
with the RI and XI bits (if they exist) in bits 63 and 62 respectively, and
|
|
the PFNX field starting at bit 30.
|
|
|
|
MIPS MAARs (see KVM_REG_MIPS_CP0_MAAR(*) above) have the following id bit
|
|
patterns::
|
|
|
|
0x7030 0000 0001 01 <reg:8>
|
|
|
|
MIPS KVM control registers (see above) have the following id bit patterns::
|
|
|
|
0x7030 0000 0002 <reg:16>
|
|
|
|
MIPS FPU registers (see KVM_REG_MIPS_FPR_{32,64}() above) have the following
|
|
id bit patterns depending on the size of the register being accessed. They are
|
|
always accessed according to the current guest FPU mode (Status.FR and
|
|
Config5.FRE), i.e. as the guest would see them, and they become unpredictable
|
|
if the guest FPU mode is changed. MIPS SIMD Architecture (MSA) vector
|
|
registers (see KVM_REG_MIPS_VEC_128() above) have similar patterns as they
|
|
overlap the FPU registers::
|
|
|
|
0x7020 0000 0003 00 <0:3> <reg:5> (32-bit FPU registers)
|
|
0x7030 0000 0003 00 <0:3> <reg:5> (64-bit FPU registers)
|
|
0x7040 0000 0003 00 <0:3> <reg:5> (128-bit MSA vector registers)
|
|
|
|
MIPS FPU control registers (see KVM_REG_MIPS_FCR_{IR,CSR} above) have the
|
|
following id bit patterns::
|
|
|
|
0x7020 0000 0003 01 <0:3> <reg:5>
|
|
|
|
MIPS MSA control registers (see KVM_REG_MIPS_MSA_{IR,CSR} above) have the
|
|
following id bit patterns::
|
|
|
|
0x7020 0000 0003 02 <0:3> <reg:5>
|
|
|
|
RISC-V registers are mapped using the lower 32 bits. The upper 8 bits of
|
|
that is the register group type.
|
|
|
|
RISC-V config registers are meant for configuring a Guest VCPU and it has
|
|
the following id bit patterns::
|
|
|
|
0x8020 0000 01 <index into the kvm_riscv_config struct:24> (32bit Host)
|
|
0x8030 0000 01 <index into the kvm_riscv_config struct:24> (64bit Host)
|
|
|
|
Following are the RISC-V config registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x80x0 0000 0100 0000 isa ISA feature bitmap of Guest VCPU
|
|
======================= ========= =============================================
|
|
|
|
The isa config register can be read anytime but can only be written before
|
|
a Guest VCPU runs. It will have ISA feature bits matching underlying host
|
|
set by default.
|
|
|
|
RISC-V core registers represent the general excution state of a Guest VCPU
|
|
and it has the following id bit patterns::
|
|
|
|
0x8020 0000 02 <index into the kvm_riscv_core struct:24> (32bit Host)
|
|
0x8030 0000 02 <index into the kvm_riscv_core struct:24> (64bit Host)
|
|
|
|
Following are the RISC-V core registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x80x0 0000 0200 0000 regs.pc Program counter
|
|
0x80x0 0000 0200 0001 regs.ra Return address
|
|
0x80x0 0000 0200 0002 regs.sp Stack pointer
|
|
0x80x0 0000 0200 0003 regs.gp Global pointer
|
|
0x80x0 0000 0200 0004 regs.tp Task pointer
|
|
0x80x0 0000 0200 0005 regs.t0 Caller saved register 0
|
|
0x80x0 0000 0200 0006 regs.t1 Caller saved register 1
|
|
0x80x0 0000 0200 0007 regs.t2 Caller saved register 2
|
|
0x80x0 0000 0200 0008 regs.s0 Callee saved register 0
|
|
0x80x0 0000 0200 0009 regs.s1 Callee saved register 1
|
|
0x80x0 0000 0200 000a regs.a0 Function argument (or return value) 0
|
|
0x80x0 0000 0200 000b regs.a1 Function argument (or return value) 1
|
|
0x80x0 0000 0200 000c regs.a2 Function argument 2
|
|
0x80x0 0000 0200 000d regs.a3 Function argument 3
|
|
0x80x0 0000 0200 000e regs.a4 Function argument 4
|
|
0x80x0 0000 0200 000f regs.a5 Function argument 5
|
|
0x80x0 0000 0200 0010 regs.a6 Function argument 6
|
|
0x80x0 0000 0200 0011 regs.a7 Function argument 7
|
|
0x80x0 0000 0200 0012 regs.s2 Callee saved register 2
|
|
0x80x0 0000 0200 0013 regs.s3 Callee saved register 3
|
|
0x80x0 0000 0200 0014 regs.s4 Callee saved register 4
|
|
0x80x0 0000 0200 0015 regs.s5 Callee saved register 5
|
|
0x80x0 0000 0200 0016 regs.s6 Callee saved register 6
|
|
0x80x0 0000 0200 0017 regs.s7 Callee saved register 7
|
|
0x80x0 0000 0200 0018 regs.s8 Callee saved register 8
|
|
0x80x0 0000 0200 0019 regs.s9 Callee saved register 9
|
|
0x80x0 0000 0200 001a regs.s10 Callee saved register 10
|
|
0x80x0 0000 0200 001b regs.s11 Callee saved register 11
|
|
0x80x0 0000 0200 001c regs.t3 Caller saved register 3
|
|
0x80x0 0000 0200 001d regs.t4 Caller saved register 4
|
|
0x80x0 0000 0200 001e regs.t5 Caller saved register 5
|
|
0x80x0 0000 0200 001f regs.t6 Caller saved register 6
|
|
0x80x0 0000 0200 0020 mode Privilege mode (1 = S-mode or 0 = U-mode)
|
|
======================= ========= =============================================
|
|
|
|
RISC-V csr registers represent the supervisor mode control/status registers
|
|
of a Guest VCPU and it has the following id bit patterns::
|
|
|
|
0x8020 0000 03 <index into the kvm_riscv_csr struct:24> (32bit Host)
|
|
0x8030 0000 03 <index into the kvm_riscv_csr struct:24> (64bit Host)
|
|
|
|
Following are the RISC-V csr registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x80x0 0000 0300 0000 sstatus Supervisor status
|
|
0x80x0 0000 0300 0001 sie Supervisor interrupt enable
|
|
0x80x0 0000 0300 0002 stvec Supervisor trap vector base
|
|
0x80x0 0000 0300 0003 sscratch Supervisor scratch register
|
|
0x80x0 0000 0300 0004 sepc Supervisor exception program counter
|
|
0x80x0 0000 0300 0005 scause Supervisor trap cause
|
|
0x80x0 0000 0300 0006 stval Supervisor bad address or instruction
|
|
0x80x0 0000 0300 0007 sip Supervisor interrupt pending
|
|
0x80x0 0000 0300 0008 satp Supervisor address translation and protection
|
|
======================= ========= =============================================
|
|
|
|
RISC-V timer registers represent the timer state of a Guest VCPU and it has
|
|
the following id bit patterns::
|
|
|
|
0x8030 0000 04 <index into the kvm_riscv_timer struct:24>
|
|
|
|
Following are the RISC-V timer registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x8030 0000 0400 0000 frequency Time base frequency (read-only)
|
|
0x8030 0000 0400 0001 time Time value visible to Guest
|
|
0x8030 0000 0400 0002 compare Time compare programmed by Guest
|
|
0x8030 0000 0400 0003 state Time compare state (1 = ON or 0 = OFF)
|
|
======================= ========= =============================================
|
|
|
|
RISC-V F-extension registers represent the single precision floating point
|
|
state of a Guest VCPU and it has the following id bit patterns::
|
|
|
|
0x8020 0000 05 <index into the __riscv_f_ext_state struct:24>
|
|
|
|
Following are the RISC-V F-extension registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x8020 0000 0500 0000 f[0] Floating point register 0
|
|
...
|
|
0x8020 0000 0500 001f f[31] Floating point register 31
|
|
0x8020 0000 0500 0020 fcsr Floating point control and status register
|
|
======================= ========= =============================================
|
|
|
|
RISC-V D-extension registers represent the double precision floating point
|
|
state of a Guest VCPU and it has the following id bit patterns::
|
|
|
|
0x8020 0000 06 <index into the __riscv_d_ext_state struct:24> (fcsr)
|
|
0x8030 0000 06 <index into the __riscv_d_ext_state struct:24> (non-fcsr)
|
|
|
|
Following are the RISC-V D-extension registers:
|
|
|
|
======================= ========= =============================================
|
|
Encoding Register Description
|
|
======================= ========= =============================================
|
|
0x8030 0000 0600 0000 f[0] Floating point register 0
|
|
...
|
|
0x8030 0000 0600 001f f[31] Floating point register 31
|
|
0x8020 0000 0600 0020 fcsr Floating point control and status register
|
|
======================= ========= =============================================
|
|
|
|
|
|
4.69 KVM_GET_ONE_REG
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_ONE_REG
|
|
:Architectures: all
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_one_reg (in and out)
|
|
:Returns: 0 on success, negative value on failure
|
|
|
|
Errors include:
|
|
|
|
======== ============================================================
|
|
ENOENT no such register
|
|
EINVAL invalid register ID, or no such register or used with VMs in
|
|
protected virtualization mode on s390
|
|
EPERM (arm64) register access not allowed before vcpu finalization
|
|
======== ============================================================
|
|
|
|
(These error codes are indicative only: do not rely on a specific error
|
|
code being returned in a specific situation.)
|
|
|
|
This ioctl allows to receive the value of a single register implemented
|
|
in a vcpu. The register to read is indicated by the "id" field of the
|
|
kvm_one_reg struct passed in. On success, the register value can be found
|
|
at the memory location pointed to by "addr".
|
|
|
|
The list of registers accessible using this interface is identical to the
|
|
list in 4.68.
|
|
|
|
|
|
4.70 KVM_KVMCLOCK_CTRL
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_KVMCLOCK_CTRL
|
|
:Architectures: Any that implement pvclocks (currently x86 only)
|
|
:Type: vcpu ioctl
|
|
:Parameters: None
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This ioctl sets a flag accessible to the guest indicating that the specified
|
|
vCPU has been paused by the host userspace.
|
|
|
|
The host will set a flag in the pvclock structure that is checked from the
|
|
soft lockup watchdog. The flag is part of the pvclock structure that is
|
|
shared between guest and host, specifically the second bit of the flags
|
|
field of the pvclock_vcpu_time_info structure. It will be set exclusively by
|
|
the host and read/cleared exclusively by the guest. The guest operation of
|
|
checking and clearing the flag must be an atomic operation so
|
|
load-link/store-conditional, or equivalent must be used. There are two cases
|
|
where the guest will clear the flag: when the soft lockup watchdog timer resets
|
|
itself or when a soft lockup is detected. This ioctl can be called any time
|
|
after pausing the vcpu, but before it is resumed.
|
|
|
|
|
|
4.71 KVM_SIGNAL_MSI
|
|
-------------------
|
|
|
|
:Capability: KVM_CAP_SIGNAL_MSI
|
|
:Architectures: x86 arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_msi (in)
|
|
:Returns: >0 on delivery, 0 if guest blocked the MSI, and -1 on error
|
|
|
|
Directly inject a MSI message. Only valid with in-kernel irqchip that handles
|
|
MSI messages.
|
|
|
|
::
|
|
|
|
struct kvm_msi {
|
|
__u32 address_lo;
|
|
__u32 address_hi;
|
|
__u32 data;
|
|
__u32 flags;
|
|
__u32 devid;
|
|
__u8 pad[12];
|
|
};
|
|
|
|
flags:
|
|
KVM_MSI_VALID_DEVID: devid contains a valid value. The per-VM
|
|
KVM_CAP_MSI_DEVID capability advertises the requirement to provide
|
|
the device ID. If this capability is not available, userspace
|
|
should never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail.
|
|
|
|
If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier
|
|
for the device that wrote the MSI message. For PCI, this is usually a
|
|
BFD identifier in the lower 16 bits.
|
|
|
|
On x86, address_hi is ignored unless the KVM_X2APIC_API_USE_32BIT_IDS
|
|
feature of KVM_CAP_X2APIC_API capability is enabled. If it is enabled,
|
|
address_hi bits 31-8 provide bits 31-8 of the destination id. Bits 7-0 of
|
|
address_hi must be zero.
|
|
|
|
|
|
4.71 KVM_CREATE_PIT2
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_PIT2
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_pit_config (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Creates an in-kernel device model for the i8254 PIT. This call is only valid
|
|
after enabling in-kernel irqchip support via KVM_CREATE_IRQCHIP. The following
|
|
parameters have to be passed::
|
|
|
|
struct kvm_pit_config {
|
|
__u32 flags;
|
|
__u32 pad[15];
|
|
};
|
|
|
|
Valid flags are::
|
|
|
|
#define KVM_PIT_SPEAKER_DUMMY 1 /* emulate speaker port stub */
|
|
|
|
PIT timer interrupts may use a per-VM kernel thread for injection. If it
|
|
exists, this thread will have a name of the following pattern::
|
|
|
|
kvm-pit/<owner-process-pid>
|
|
|
|
When running a guest with elevated priorities, the scheduling parameters of
|
|
this thread may have to be adjusted accordingly.
|
|
|
|
This IOCTL replaces the obsolete KVM_CREATE_PIT.
|
|
|
|
|
|
4.72 KVM_GET_PIT2
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_PIT_STATE2
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_pit_state2 (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Retrieves the state of the in-kernel PIT model. Only valid after
|
|
KVM_CREATE_PIT2. The state is returned in the following structure::
|
|
|
|
struct kvm_pit_state2 {
|
|
struct kvm_pit_channel_state channels[3];
|
|
__u32 flags;
|
|
__u32 reserved[9];
|
|
};
|
|
|
|
Valid flags are::
|
|
|
|
/* disable PIT in HPET legacy mode */
|
|
#define KVM_PIT_FLAGS_HPET_LEGACY 0x00000001
|
|
/* speaker port data bit enabled */
|
|
#define KVM_PIT_FLAGS_SPEAKER_DATA_ON 0x00000002
|
|
|
|
This IOCTL replaces the obsolete KVM_GET_PIT.
|
|
|
|
|
|
4.73 KVM_SET_PIT2
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_PIT_STATE2
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_pit_state2 (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Sets the state of the in-kernel PIT model. Only valid after KVM_CREATE_PIT2.
|
|
See KVM_GET_PIT2 for details on struct kvm_pit_state2.
|
|
|
|
This IOCTL replaces the obsolete KVM_SET_PIT.
|
|
|
|
|
|
4.74 KVM_PPC_GET_SMMU_INFO
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_GET_SMMU_INFO
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: None
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This populates and returns a structure describing the features of
|
|
the "Server" class MMU emulation supported by KVM.
|
|
This can in turn be used by userspace to generate the appropriate
|
|
device-tree properties for the guest operating system.
|
|
|
|
The structure contains some global information, followed by an
|
|
array of supported segment page sizes::
|
|
|
|
struct kvm_ppc_smmu_info {
|
|
__u64 flags;
|
|
__u32 slb_size;
|
|
__u32 pad;
|
|
struct kvm_ppc_one_seg_page_size sps[KVM_PPC_PAGE_SIZES_MAX_SZ];
|
|
};
|
|
|
|
The supported flags are:
|
|
|
|
- KVM_PPC_PAGE_SIZES_REAL:
|
|
When that flag is set, guest page sizes must "fit" the backing
|
|
store page sizes. When not set, any page size in the list can
|
|
be used regardless of how they are backed by userspace.
|
|
|
|
- KVM_PPC_1T_SEGMENTS
|
|
The emulated MMU supports 1T segments in addition to the
|
|
standard 256M ones.
|
|
|
|
- KVM_PPC_NO_HASH
|
|
This flag indicates that HPT guests are not supported by KVM,
|
|
thus all guests must use radix MMU mode.
|
|
|
|
The "slb_size" field indicates how many SLB entries are supported
|
|
|
|
The "sps" array contains 8 entries indicating the supported base
|
|
page sizes for a segment in increasing order. Each entry is defined
|
|
as follow::
|
|
|
|
struct kvm_ppc_one_seg_page_size {
|
|
__u32 page_shift; /* Base page shift of segment (or 0) */
|
|
__u32 slb_enc; /* SLB encoding for BookS */
|
|
struct kvm_ppc_one_page_size enc[KVM_PPC_PAGE_SIZES_MAX_SZ];
|
|
};
|
|
|
|
An entry with a "page_shift" of 0 is unused. Because the array is
|
|
organized in increasing order, a lookup can stop when encoutering
|
|
such an entry.
|
|
|
|
The "slb_enc" field provides the encoding to use in the SLB for the
|
|
page size. The bits are in positions such as the value can directly
|
|
be OR'ed into the "vsid" argument of the slbmte instruction.
|
|
|
|
The "enc" array is a list which for each of those segment base page
|
|
size provides the list of supported actual page sizes (which can be
|
|
only larger or equal to the base page size), along with the
|
|
corresponding encoding in the hash PTE. Similarly, the array is
|
|
8 entries sorted by increasing sizes and an entry with a "0" shift
|
|
is an empty entry and a terminator::
|
|
|
|
struct kvm_ppc_one_page_size {
|
|
__u32 page_shift; /* Page shift (or 0) */
|
|
__u32 pte_enc; /* Encoding in the HPTE (>>12) */
|
|
};
|
|
|
|
The "pte_enc" field provides a value that can OR'ed into the hash
|
|
PTE's RPN field (ie, it needs to be shifted left by 12 to OR it
|
|
into the hash PTE second double word).
|
|
|
|
4.75 KVM_IRQFD
|
|
--------------
|
|
|
|
:Capability: KVM_CAP_IRQFD
|
|
:Architectures: x86 s390 arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irqfd (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Allows setting an eventfd to directly trigger a guest interrupt.
|
|
kvm_irqfd.fd specifies the file descriptor to use as the eventfd and
|
|
kvm_irqfd.gsi specifies the irqchip pin toggled by this event. When
|
|
an event is triggered on the eventfd, an interrupt is injected into
|
|
the guest using the specified gsi pin. The irqfd is removed using
|
|
the KVM_IRQFD_FLAG_DEASSIGN flag, specifying both kvm_irqfd.fd
|
|
and kvm_irqfd.gsi.
|
|
|
|
With KVM_CAP_IRQFD_RESAMPLE, KVM_IRQFD supports a de-assert and notify
|
|
mechanism allowing emulation of level-triggered, irqfd-based
|
|
interrupts. When KVM_IRQFD_FLAG_RESAMPLE is set the user must pass an
|
|
additional eventfd in the kvm_irqfd.resamplefd field. When operating
|
|
in resample mode, posting of an interrupt through kvm_irq.fd asserts
|
|
the specified gsi in the irqchip. When the irqchip is resampled, such
|
|
as from an EOI, the gsi is de-asserted and the user is notified via
|
|
kvm_irqfd.resamplefd. It is the user's responsibility to re-queue
|
|
the interrupt if the device making use of it still requires service.
|
|
Note that closing the resamplefd is not sufficient to disable the
|
|
irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment
|
|
and need not be specified with KVM_IRQFD_FLAG_DEASSIGN.
|
|
|
|
On arm64, gsi routing being supported, the following can happen:
|
|
|
|
- in case no routing entry is associated to this gsi, injection fails
|
|
- in case the gsi is associated to an irqchip routing entry,
|
|
irqchip.pin + 32 corresponds to the injected SPI ID.
|
|
- in case the gsi is associated to an MSI routing entry, the MSI
|
|
message and device ID are translated into an LPI (support restricted
|
|
to GICv3 ITS in-kernel emulation).
|
|
|
|
4.76 KVM_PPC_ALLOCATE_HTAB
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_ALLOC_HTAB
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: Pointer to u32 containing hash table order (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This requests the host kernel to allocate an MMU hash table for a
|
|
guest using the PAPR paravirtualization interface. This only does
|
|
anything if the kernel is configured to use the Book 3S HV style of
|
|
virtualization. Otherwise the capability doesn't exist and the ioctl
|
|
returns an ENOTTY error. The rest of this description assumes Book 3S
|
|
HV.
|
|
|
|
There must be no vcpus running when this ioctl is called; if there
|
|
are, it will do nothing and return an EBUSY error.
|
|
|
|
The parameter is a pointer to a 32-bit unsigned integer variable
|
|
containing the order (log base 2) of the desired size of the hash
|
|
table, which must be between 18 and 46. On successful return from the
|
|
ioctl, the value will not be changed by the kernel.
|
|
|
|
If no hash table has been allocated when any vcpu is asked to run
|
|
(with the KVM_RUN ioctl), the host kernel will allocate a
|
|
default-sized hash table (16 MB).
|
|
|
|
If this ioctl is called when a hash table has already been allocated,
|
|
with a different order from the existing hash table, the existing hash
|
|
table will be freed and a new one allocated. If this is ioctl is
|
|
called when a hash table has already been allocated of the same order
|
|
as specified, the kernel will clear out the existing hash table (zero
|
|
all HPTEs). In either case, if the guest is using the virtualized
|
|
real-mode area (VRMA) facility, the kernel will re-create the VMRA
|
|
HPTEs on the next KVM_RUN of any vcpu.
|
|
|
|
4.77 KVM_S390_INTERRUPT
|
|
-----------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: s390
|
|
:Type: vm ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_s390_interrupt (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Allows to inject an interrupt to the guest. Interrupts can be floating
|
|
(vm ioctl) or per cpu (vcpu ioctl), depending on the interrupt type.
|
|
|
|
Interrupt parameters are passed via kvm_s390_interrupt::
|
|
|
|
struct kvm_s390_interrupt {
|
|
__u32 type;
|
|
__u32 parm;
|
|
__u64 parm64;
|
|
};
|
|
|
|
type can be one of the following:
|
|
|
|
KVM_S390_SIGP_STOP (vcpu)
|
|
- sigp stop; optional flags in parm
|
|
KVM_S390_PROGRAM_INT (vcpu)
|
|
- program check; code in parm
|
|
KVM_S390_SIGP_SET_PREFIX (vcpu)
|
|
- sigp set prefix; prefix address in parm
|
|
KVM_S390_RESTART (vcpu)
|
|
- restart
|
|
KVM_S390_INT_CLOCK_COMP (vcpu)
|
|
- clock comparator interrupt
|
|
KVM_S390_INT_CPU_TIMER (vcpu)
|
|
- CPU timer interrupt
|
|
KVM_S390_INT_VIRTIO (vm)
|
|
- virtio external interrupt; external interrupt
|
|
parameters in parm and parm64
|
|
KVM_S390_INT_SERVICE (vm)
|
|
- sclp external interrupt; sclp parameter in parm
|
|
KVM_S390_INT_EMERGENCY (vcpu)
|
|
- sigp emergency; source cpu in parm
|
|
KVM_S390_INT_EXTERNAL_CALL (vcpu)
|
|
- sigp external call; source cpu in parm
|
|
KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm)
|
|
- compound value to indicate an
|
|
I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel);
|
|
I/O interruption parameters in parm (subchannel) and parm64 (intparm,
|
|
interruption subclass)
|
|
KVM_S390_MCHK (vm, vcpu)
|
|
- machine check interrupt; cr 14 bits in parm, machine check interrupt
|
|
code in parm64 (note that machine checks needing further payload are not
|
|
supported by this ioctl)
|
|
|
|
This is an asynchronous vcpu ioctl and can be invoked from any thread.
|
|
|
|
4.78 KVM_PPC_GET_HTAB_FD
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_HTAB_FD
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: Pointer to struct kvm_get_htab_fd (in)
|
|
:Returns: file descriptor number (>= 0) on success, -1 on error
|
|
|
|
This returns a file descriptor that can be used either to read out the
|
|
entries in the guest's hashed page table (HPT), or to write entries to
|
|
initialize the HPT. The returned fd can only be written to if the
|
|
KVM_GET_HTAB_WRITE bit is set in the flags field of the argument, and
|
|
can only be read if that bit is clear. The argument struct looks like
|
|
this::
|
|
|
|
/* For KVM_PPC_GET_HTAB_FD */
|
|
struct kvm_get_htab_fd {
|
|
__u64 flags;
|
|
__u64 start_index;
|
|
__u64 reserved[2];
|
|
};
|
|
|
|
/* Values for kvm_get_htab_fd.flags */
|
|
#define KVM_GET_HTAB_BOLTED_ONLY ((__u64)0x1)
|
|
#define KVM_GET_HTAB_WRITE ((__u64)0x2)
|
|
|
|
The 'start_index' field gives the index in the HPT of the entry at
|
|
which to start reading. It is ignored when writing.
|
|
|
|
Reads on the fd will initially supply information about all
|
|
"interesting" HPT entries. Interesting entries are those with the
|
|
bolted bit set, if the KVM_GET_HTAB_BOLTED_ONLY bit is set, otherwise
|
|
all entries. When the end of the HPT is reached, the read() will
|
|
return. If read() is called again on the fd, it will start again from
|
|
the beginning of the HPT, but will only return HPT entries that have
|
|
changed since they were last read.
|
|
|
|
Data read or written is structured as a header (8 bytes) followed by a
|
|
series of valid HPT entries (16 bytes) each. The header indicates how
|
|
many valid HPT entries there are and how many invalid entries follow
|
|
the valid entries. The invalid entries are not represented explicitly
|
|
in the stream. The header format is::
|
|
|
|
struct kvm_get_htab_header {
|
|
__u32 index;
|
|
__u16 n_valid;
|
|
__u16 n_invalid;
|
|
};
|
|
|
|
Writes to the fd create HPT entries starting at the index given in the
|
|
header; first 'n_valid' valid entries with contents from the data
|
|
written, then 'n_invalid' invalid entries, invalidating any previously
|
|
valid entries found.
|
|
|
|
4.79 KVM_CREATE_DEVICE
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_DEVICE_CTRL
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_create_device (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
====== =======================================================
|
|
ENODEV The device type is unknown or unsupported
|
|
EEXIST Device already created, and this type of device may not
|
|
be instantiated multiple times
|
|
====== =======================================================
|
|
|
|
Other error conditions may be defined by individual device types or
|
|
have their standard meanings.
|
|
|
|
Creates an emulated device in the kernel. The file descriptor returned
|
|
in fd can be used with KVM_SET/GET/HAS_DEVICE_ATTR.
|
|
|
|
If the KVM_CREATE_DEVICE_TEST flag is set, only test whether the
|
|
device type is supported (not necessarily whether it can be created
|
|
in the current vm).
|
|
|
|
Individual devices should not define flags. Attributes should be used
|
|
for specifying any behavior that is not implied by the device type
|
|
number.
|
|
|
|
::
|
|
|
|
struct kvm_create_device {
|
|
__u32 type; /* in: KVM_DEV_TYPE_xxx */
|
|
__u32 fd; /* out: device handle */
|
|
__u32 flags; /* in: KVM_CREATE_DEVICE_xxx */
|
|
};
|
|
|
|
4.80 KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR
|
|
--------------------------------------------
|
|
|
|
:Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device,
|
|
KVM_CAP_VCPU_ATTRIBUTES for vcpu device
|
|
KVM_CAP_SYS_ATTRIBUTES for system (/dev/kvm) device (no set)
|
|
:Type: device ioctl, vm ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_device_attr
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
===== =============================================================
|
|
ENXIO The group or attribute is unknown/unsupported for this device
|
|
or hardware support is missing.
|
|
EPERM The attribute cannot (currently) be accessed this way
|
|
(e.g. read-only attribute, or attribute that only makes
|
|
sense when the device is in a different state)
|
|
===== =============================================================
|
|
|
|
Other error conditions may be defined by individual device types.
|
|
|
|
Gets/sets a specified piece of device configuration and/or state. The
|
|
semantics are device-specific. See individual device documentation in
|
|
the "devices" directory. As with ONE_REG, the size of the data
|
|
transferred is defined by the particular attribute.
|
|
|
|
::
|
|
|
|
struct kvm_device_attr {
|
|
__u32 flags; /* no flags currently defined */
|
|
__u32 group; /* device-defined */
|
|
__u64 attr; /* group-defined */
|
|
__u64 addr; /* userspace address of attr data */
|
|
};
|
|
|
|
4.81 KVM_HAS_DEVICE_ATTR
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device,
|
|
KVM_CAP_VCPU_ATTRIBUTES for vcpu device
|
|
KVM_CAP_SYS_ATTRIBUTES for system (/dev/kvm) device
|
|
:Type: device ioctl, vm ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_device_attr
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
===== =============================================================
|
|
ENXIO The group or attribute is unknown/unsupported for this device
|
|
or hardware support is missing.
|
|
===== =============================================================
|
|
|
|
Tests whether a device supports a particular attribute. A successful
|
|
return indicates the attribute is implemented. It does not necessarily
|
|
indicate that the attribute can be read or written in the device's
|
|
current state. "addr" is ignored.
|
|
|
|
4.82 KVM_ARM_VCPU_INIT
|
|
----------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: arm64
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_vcpu_init (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
Errors:
|
|
|
|
====== =================================================================
|
|
EINVAL the target is unknown, or the combination of features is invalid.
|
|
ENOENT a features bit specified is unknown.
|
|
====== =================================================================
|
|
|
|
This tells KVM what type of CPU to present to the guest, and what
|
|
optional features it should have. This will cause a reset of the cpu
|
|
registers to their initial values. If this is not called, KVM_RUN will
|
|
return ENOEXEC for that vcpu.
|
|
|
|
The initial values are defined as:
|
|
- Processor state:
|
|
* AArch64: EL1h, D, A, I and F bits set. All other bits
|
|
are cleared.
|
|
* AArch32: SVC, A, I and F bits set. All other bits are
|
|
cleared.
|
|
- General Purpose registers, including PC and SP: set to 0
|
|
- FPSIMD/NEON registers: set to 0
|
|
- SVE registers: set to 0
|
|
- System registers: Reset to their architecturally defined
|
|
values as for a warm reset to EL1 (resp. SVC)
|
|
|
|
Note that because some registers reflect machine topology, all vcpus
|
|
should be created before this ioctl is invoked.
|
|
|
|
Userspace can call this function multiple times for a given vcpu, including
|
|
after the vcpu has been run. This will reset the vcpu to its initial
|
|
state. All calls to this function after the initial call must use the same
|
|
target and same set of feature flags, otherwise EINVAL will be returned.
|
|
|
|
Possible features:
|
|
|
|
- KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state.
|
|
Depends on KVM_CAP_ARM_PSCI. If not set, the CPU will be powered on
|
|
and execute guest code when KVM_RUN is called.
|
|
- KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode.
|
|
Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only).
|
|
- KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 (or a future revision
|
|
backward compatible with v0.2) for the CPU.
|
|
Depends on KVM_CAP_ARM_PSCI_0_2.
|
|
- KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU.
|
|
Depends on KVM_CAP_ARM_PMU_V3.
|
|
|
|
- KVM_ARM_VCPU_PTRAUTH_ADDRESS: Enables Address Pointer authentication
|
|
for arm64 only.
|
|
Depends on KVM_CAP_ARM_PTRAUTH_ADDRESS.
|
|
If KVM_CAP_ARM_PTRAUTH_ADDRESS and KVM_CAP_ARM_PTRAUTH_GENERIC are
|
|
both present, then both KVM_ARM_VCPU_PTRAUTH_ADDRESS and
|
|
KVM_ARM_VCPU_PTRAUTH_GENERIC must be requested or neither must be
|
|
requested.
|
|
|
|
- KVM_ARM_VCPU_PTRAUTH_GENERIC: Enables Generic Pointer authentication
|
|
for arm64 only.
|
|
Depends on KVM_CAP_ARM_PTRAUTH_GENERIC.
|
|
If KVM_CAP_ARM_PTRAUTH_ADDRESS and KVM_CAP_ARM_PTRAUTH_GENERIC are
|
|
both present, then both KVM_ARM_VCPU_PTRAUTH_ADDRESS and
|
|
KVM_ARM_VCPU_PTRAUTH_GENERIC must be requested or neither must be
|
|
requested.
|
|
|
|
- KVM_ARM_VCPU_SVE: Enables SVE for the CPU (arm64 only).
|
|
Depends on KVM_CAP_ARM_SVE.
|
|
Requires KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
|
|
|
|
* After KVM_ARM_VCPU_INIT:
|
|
|
|
- KVM_REG_ARM64_SVE_VLS may be read using KVM_GET_ONE_REG: the
|
|
initial value of this pseudo-register indicates the best set of
|
|
vector lengths possible for a vcpu on this host.
|
|
|
|
* Before KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
|
|
|
|
- KVM_RUN and KVM_GET_REG_LIST are not available;
|
|
|
|
- KVM_GET_ONE_REG and KVM_SET_ONE_REG cannot be used to access
|
|
the scalable archietctural SVE registers
|
|
KVM_REG_ARM64_SVE_ZREG(), KVM_REG_ARM64_SVE_PREG() or
|
|
KVM_REG_ARM64_SVE_FFR;
|
|
|
|
- KVM_REG_ARM64_SVE_VLS may optionally be written using
|
|
KVM_SET_ONE_REG, to modify the set of vector lengths available
|
|
for the vcpu.
|
|
|
|
* After KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
|
|
|
|
- the KVM_REG_ARM64_SVE_VLS pseudo-register is immutable, and can
|
|
no longer be written using KVM_SET_ONE_REG.
|
|
|
|
4.83 KVM_ARM_PREFERRED_TARGET
|
|
-----------------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_vcpu_init (out)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
Errors:
|
|
|
|
====== ==========================================
|
|
ENODEV no preferred target available for the host
|
|
====== ==========================================
|
|
|
|
This queries KVM for preferred CPU target type which can be emulated
|
|
by KVM on underlying host.
|
|
|
|
The ioctl returns struct kvm_vcpu_init instance containing information
|
|
about preferred CPU target type and recommended features for it. The
|
|
kvm_vcpu_init->features bitmap returned will have feature bits set if
|
|
the preferred target recommends setting these features, but this is
|
|
not mandatory.
|
|
|
|
The information returned by this ioctl can be used to prepare an instance
|
|
of struct kvm_vcpu_init for KVM_ARM_VCPU_INIT ioctl which will result in
|
|
VCPU matching underlying host.
|
|
|
|
|
|
4.84 KVM_GET_REG_LIST
|
|
---------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: arm64, mips
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_reg_list (in/out)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
Errors:
|
|
|
|
===== ==============================================================
|
|
E2BIG the reg index list is too big to fit in the array specified by
|
|
the user (the number required will be written into n).
|
|
===== ==============================================================
|
|
|
|
::
|
|
|
|
struct kvm_reg_list {
|
|
__u64 n; /* number of registers in reg[] */
|
|
__u64 reg[0];
|
|
};
|
|
|
|
This ioctl returns the guest registers that are supported for the
|
|
KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
|
|
|
|
|
|
4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated)
|
|
-----------------------------------------
|
|
|
|
:Capability: KVM_CAP_ARM_SET_DEVICE_ADDR
|
|
:Architectures: arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_arm_device_address (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
====== ============================================
|
|
ENODEV The device id is unknown
|
|
ENXIO Device not supported on current system
|
|
EEXIST Address already set
|
|
E2BIG Address outside guest physical address space
|
|
EBUSY Address overlaps with other device range
|
|
====== ============================================
|
|
|
|
::
|
|
|
|
struct kvm_arm_device_addr {
|
|
__u64 id;
|
|
__u64 addr;
|
|
};
|
|
|
|
Specify a device address in the guest's physical address space where guests
|
|
can access emulated or directly exposed devices, which the host kernel needs
|
|
to know about. The id field is an architecture specific identifier for a
|
|
specific device.
|
|
|
|
arm64 divides the id field into two parts, a device id and an
|
|
address type id specific to the individual device::
|
|
|
|
bits: | 63 ... 32 | 31 ... 16 | 15 ... 0 |
|
|
field: | 0x00000000 | device id | addr type id |
|
|
|
|
arm64 currently only require this when using the in-kernel GIC
|
|
support for the hardware VGIC features, using KVM_ARM_DEVICE_VGIC_V2
|
|
as the device id. When setting the base address for the guest's
|
|
mapping of the VGIC virtual CPU and distributor interface, the ioctl
|
|
must be called after calling KVM_CREATE_IRQCHIP, but before calling
|
|
KVM_RUN on any of the VCPUs. Calling this ioctl twice for any of the
|
|
base addresses will return -EEXIST.
|
|
|
|
Note, this IOCTL is deprecated and the more flexible SET/GET_DEVICE_ATTR API
|
|
should be used instead.
|
|
|
|
|
|
4.86 KVM_PPC_RTAS_DEFINE_TOKEN
|
|
------------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_RTAS
|
|
:Architectures: ppc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_rtas_token_args
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Defines a token value for a RTAS (Run Time Abstraction Services)
|
|
service in order to allow it to be handled in the kernel. The
|
|
argument struct gives the name of the service, which must be the name
|
|
of a service that has a kernel-side implementation. If the token
|
|
value is non-zero, it will be associated with that service, and
|
|
subsequent RTAS calls by the guest specifying that token will be
|
|
handled by the kernel. If the token value is 0, then any token
|
|
associated with the service will be forgotten, and subsequent RTAS
|
|
calls by the guest for that service will be passed to userspace to be
|
|
handled.
|
|
|
|
4.87 KVM_SET_GUEST_DEBUG
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_SET_GUEST_DEBUG
|
|
:Architectures: x86, s390, ppc, arm64
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_guest_debug (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_guest_debug {
|
|
__u32 control;
|
|
__u32 pad;
|
|
struct kvm_guest_debug_arch arch;
|
|
};
|
|
|
|
Set up the processor specific debug registers and configure vcpu for
|
|
handling guest debug events. There are two parts to the structure, the
|
|
first a control bitfield indicates the type of debug events to handle
|
|
when running. Common control bits are:
|
|
|
|
- KVM_GUESTDBG_ENABLE: guest debugging is enabled
|
|
- KVM_GUESTDBG_SINGLESTEP: the next run should single-step
|
|
|
|
The top 16 bits of the control field are architecture specific control
|
|
flags which can include the following:
|
|
|
|
- KVM_GUESTDBG_USE_SW_BP: using software breakpoints [x86, arm64]
|
|
- KVM_GUESTDBG_USE_HW_BP: using hardware breakpoints [x86, s390]
|
|
- KVM_GUESTDBG_USE_HW: using hardware debug events [arm64]
|
|
- KVM_GUESTDBG_INJECT_DB: inject DB type exception [x86]
|
|
- KVM_GUESTDBG_INJECT_BP: inject BP type exception [x86]
|
|
- KVM_GUESTDBG_EXIT_PENDING: trigger an immediate guest exit [s390]
|
|
- KVM_GUESTDBG_BLOCKIRQ: avoid injecting interrupts/NMI/SMI [x86]
|
|
|
|
For example KVM_GUESTDBG_USE_SW_BP indicates that software breakpoints
|
|
are enabled in memory so we need to ensure breakpoint exceptions are
|
|
correctly trapped and the KVM run loop exits at the breakpoint and not
|
|
running off into the normal guest vector. For KVM_GUESTDBG_USE_HW_BP
|
|
we need to ensure the guest vCPUs architecture specific registers are
|
|
updated to the correct (supplied) values.
|
|
|
|
The second part of the structure is architecture specific and
|
|
typically contains a set of debug registers.
|
|
|
|
For arm64 the number of debug registers is implementation defined and
|
|
can be determined by querying the KVM_CAP_GUEST_DEBUG_HW_BPS and
|
|
KVM_CAP_GUEST_DEBUG_HW_WPS capabilities which return a positive number
|
|
indicating the number of supported registers.
|
|
|
|
For ppc, the KVM_CAP_PPC_GUEST_DEBUG_SSTEP capability indicates whether
|
|
the single-step debug event (KVM_GUESTDBG_SINGLESTEP) is supported.
|
|
|
|
Also when supported, KVM_CAP_SET_GUEST_DEBUG2 capability indicates the
|
|
supported KVM_GUESTDBG_* bits in the control field.
|
|
|
|
When debug events exit the main run loop with the reason
|
|
KVM_EXIT_DEBUG with the kvm_debug_exit_arch part of the kvm_run
|
|
structure containing architecture specific debug information.
|
|
|
|
4.88 KVM_GET_EMULATED_CPUID
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_EXT_EMUL_CPUID
|
|
:Architectures: x86
|
|
:Type: system ioctl
|
|
:Parameters: struct kvm_cpuid2 (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_cpuid2 {
|
|
__u32 nent;
|
|
__u32 flags;
|
|
struct kvm_cpuid_entry2 entries[0];
|
|
};
|
|
|
|
The member 'flags' is used for passing flags from userspace.
|
|
|
|
::
|
|
|
|
#define KVM_CPUID_FLAG_SIGNIFCANT_INDEX BIT(0)
|
|
#define KVM_CPUID_FLAG_STATEFUL_FUNC BIT(1) /* deprecated */
|
|
#define KVM_CPUID_FLAG_STATE_READ_NEXT BIT(2) /* deprecated */
|
|
|
|
struct kvm_cpuid_entry2 {
|
|
__u32 function;
|
|
__u32 index;
|
|
__u32 flags;
|
|
__u32 eax;
|
|
__u32 ebx;
|
|
__u32 ecx;
|
|
__u32 edx;
|
|
__u32 padding[3];
|
|
};
|
|
|
|
This ioctl returns x86 cpuid features which are emulated by
|
|
kvm.Userspace can use the information returned by this ioctl to query
|
|
which features are emulated by kvm instead of being present natively.
|
|
|
|
Userspace invokes KVM_GET_EMULATED_CPUID by passing a kvm_cpuid2
|
|
structure with the 'nent' field indicating the number of entries in
|
|
the variable-size array 'entries'. If the number of entries is too low
|
|
to describe the cpu capabilities, an error (E2BIG) is returned. If the
|
|
number is too high, the 'nent' field is adjusted and an error (ENOMEM)
|
|
is returned. If the number is just right, the 'nent' field is adjusted
|
|
to the number of valid entries in the 'entries' array, which is then
|
|
filled.
|
|
|
|
The entries returned are the set CPUID bits of the respective features
|
|
which kvm emulates, as returned by the CPUID instruction, with unknown
|
|
or unsupported feature bits cleared.
|
|
|
|
Features like x2apic, for example, may not be present in the host cpu
|
|
but are exposed by kvm in KVM_GET_SUPPORTED_CPUID because they can be
|
|
emulated efficiently and thus not included here.
|
|
|
|
The fields in each entry are defined as follows:
|
|
|
|
function:
|
|
the eax value used to obtain the entry
|
|
index:
|
|
the ecx value used to obtain the entry (for entries that are
|
|
affected by ecx)
|
|
flags:
|
|
an OR of zero or more of the following:
|
|
|
|
KVM_CPUID_FLAG_SIGNIFCANT_INDEX:
|
|
if the index field is valid
|
|
|
|
eax, ebx, ecx, edx:
|
|
|
|
the values returned by the cpuid instruction for
|
|
this function/index combination
|
|
|
|
4.89 KVM_S390_MEM_OP
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_S390_MEM_OP, KVM_CAP_S390_PROTECTED, KVM_CAP_S390_MEM_OP_EXTENSION
|
|
:Architectures: s390
|
|
:Type: vm ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_s390_mem_op (in)
|
|
:Returns: = 0 on success,
|
|
< 0 on generic error (e.g. -EFAULT or -ENOMEM),
|
|
> 0 if an exception occurred while walking the page tables
|
|
|
|
Read or write data from/to the VM's memory.
|
|
The KVM_CAP_S390_MEM_OP_EXTENSION capability specifies what functionality is
|
|
supported.
|
|
|
|
Parameters are specified via the following structure::
|
|
|
|
struct kvm_s390_mem_op {
|
|
__u64 gaddr; /* the guest address */
|
|
__u64 flags; /* flags */
|
|
__u32 size; /* amount of bytes */
|
|
__u32 op; /* type of operation */
|
|
__u64 buf; /* buffer in userspace */
|
|
union {
|
|
struct {
|
|
__u8 ar; /* the access register number */
|
|
__u8 key; /* access key, ignored if flag unset */
|
|
};
|
|
__u32 sida_offset; /* offset into the sida */
|
|
__u8 reserved[32]; /* ignored */
|
|
};
|
|
};
|
|
|
|
The start address of the memory region has to be specified in the "gaddr"
|
|
field, and the length of the region in the "size" field (which must not
|
|
be 0). The maximum value for "size" can be obtained by checking the
|
|
KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
|
|
userspace application where the read data should be written to for
|
|
a read access, or where the data that should be written is stored for
|
|
a write access. The "reserved" field is meant for future extensions.
|
|
Reserved and unused values are ignored. Future extension that add members must
|
|
introduce new flags.
|
|
|
|
The type of operation is specified in the "op" field. Flags modifying
|
|
their behavior can be set in the "flags" field. Undefined flag bits must
|
|
be set to 0.
|
|
|
|
Possible operations are:
|
|
* ``KVM_S390_MEMOP_LOGICAL_READ``
|
|
* ``KVM_S390_MEMOP_LOGICAL_WRITE``
|
|
* ``KVM_S390_MEMOP_ABSOLUTE_READ``
|
|
* ``KVM_S390_MEMOP_ABSOLUTE_WRITE``
|
|
* ``KVM_S390_MEMOP_SIDA_READ``
|
|
* ``KVM_S390_MEMOP_SIDA_WRITE``
|
|
|
|
Logical read/write:
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
Access logical memory, i.e. translate the given guest address to an absolute
|
|
address given the state of the VCPU and use the absolute address as target of
|
|
the access. "ar" designates the access register number to be used; the valid
|
|
range is 0..15.
|
|
Logical accesses are permitted for the VCPU ioctl only.
|
|
Logical accesses are permitted for non-protected guests only.
|
|
|
|
Supported flags:
|
|
* ``KVM_S390_MEMOP_F_CHECK_ONLY``
|
|
* ``KVM_S390_MEMOP_F_INJECT_EXCEPTION``
|
|
* ``KVM_S390_MEMOP_F_SKEY_PROTECTION``
|
|
|
|
The KVM_S390_MEMOP_F_CHECK_ONLY flag can be set to check whether the
|
|
corresponding memory access would cause an access exception; however,
|
|
no actual access to the data in memory at the destination is performed.
|
|
In this case, "buf" is unused and can be NULL.
|
|
|
|
In case an access exception occurred during the access (or would occur
|
|
in case of KVM_S390_MEMOP_F_CHECK_ONLY), the ioctl returns a positive
|
|
error number indicating the type of exception. This exception is also
|
|
raised directly at the corresponding VCPU if the flag
|
|
KVM_S390_MEMOP_F_INJECT_EXCEPTION is set.
|
|
On protection exceptions, unless specified otherwise, the injected
|
|
translation-exception identifier (TEID) indicates suppression.
|
|
|
|
If the KVM_S390_MEMOP_F_SKEY_PROTECTION flag is set, storage key
|
|
protection is also in effect and may cause exceptions if accesses are
|
|
prohibited given the access key designated by "key"; the valid range is 0..15.
|
|
KVM_S390_MEMOP_F_SKEY_PROTECTION is available if KVM_CAP_S390_MEM_OP_EXTENSION
|
|
is > 0.
|
|
Since the accessed memory may span multiple pages and those pages might have
|
|
different storage keys, it is possible that a protection exception occurs
|
|
after memory has been modified. In this case, if the exception is injected,
|
|
the TEID does not indicate suppression.
|
|
|
|
Absolute read/write:
|
|
^^^^^^^^^^^^^^^^^^^^
|
|
|
|
Access absolute memory. This operation is intended to be used with the
|
|
KVM_S390_MEMOP_F_SKEY_PROTECTION flag, to allow accessing memory and performing
|
|
the checks required for storage key protection as one operation (as opposed to
|
|
user space getting the storage keys, performing the checks, and accessing
|
|
memory thereafter, which could lead to a delay between check and access).
|
|
Absolute accesses are permitted for the VM ioctl if KVM_CAP_S390_MEM_OP_EXTENSION
|
|
is > 0.
|
|
Currently absolute accesses are not permitted for VCPU ioctls.
|
|
Absolute accesses are permitted for non-protected guests only.
|
|
|
|
Supported flags:
|
|
* ``KVM_S390_MEMOP_F_CHECK_ONLY``
|
|
* ``KVM_S390_MEMOP_F_SKEY_PROTECTION``
|
|
|
|
The semantics of the flags are as for logical accesses.
|
|
|
|
SIDA read/write:
|
|
^^^^^^^^^^^^^^^^
|
|
|
|
Access the secure instruction data area which contains memory operands necessary
|
|
for instruction emulation for protected guests.
|
|
SIDA accesses are available if the KVM_CAP_S390_PROTECTED capability is available.
|
|
SIDA accesses are permitted for the VCPU ioctl only.
|
|
SIDA accesses are permitted for protected guests only.
|
|
|
|
No flags are supported.
|
|
|
|
4.90 KVM_S390_GET_SKEYS
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_S390_SKEYS
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_s390_skeys
|
|
:Returns: 0 on success, KVM_S390_GET_SKEYS_NONE if guest is not using storage
|
|
keys, negative value on error
|
|
|
|
This ioctl is used to get guest storage key values on the s390
|
|
architecture. The ioctl takes parameters via the kvm_s390_skeys struct::
|
|
|
|
struct kvm_s390_skeys {
|
|
__u64 start_gfn;
|
|
__u64 count;
|
|
__u64 skeydata_addr;
|
|
__u32 flags;
|
|
__u32 reserved[9];
|
|
};
|
|
|
|
The start_gfn field is the number of the first guest frame whose storage keys
|
|
you want to get.
|
|
|
|
The count field is the number of consecutive frames (starting from start_gfn)
|
|
whose storage keys to get. The count field must be at least 1 and the maximum
|
|
allowed value is defined as KVM_S390_SKEYS_MAX. Values outside this range
|
|
will cause the ioctl to return -EINVAL.
|
|
|
|
The skeydata_addr field is the address to a buffer large enough to hold count
|
|
bytes. This buffer will be filled with storage key data by the ioctl.
|
|
|
|
4.91 KVM_S390_SET_SKEYS
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_S390_SKEYS
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_s390_skeys
|
|
:Returns: 0 on success, negative value on error
|
|
|
|
This ioctl is used to set guest storage key values on the s390
|
|
architecture. The ioctl takes parameters via the kvm_s390_skeys struct.
|
|
See section on KVM_S390_GET_SKEYS for struct definition.
|
|
|
|
The start_gfn field is the number of the first guest frame whose storage keys
|
|
you want to set.
|
|
|
|
The count field is the number of consecutive frames (starting from start_gfn)
|
|
whose storage keys to get. The count field must be at least 1 and the maximum
|
|
allowed value is defined as KVM_S390_SKEYS_MAX. Values outside this range
|
|
will cause the ioctl to return -EINVAL.
|
|
|
|
The skeydata_addr field is the address to a buffer containing count bytes of
|
|
storage keys. Each byte in the buffer will be set as the storage key for a
|
|
single frame starting at start_gfn for count frames.
|
|
|
|
Note: If any architecturally invalid key value is found in the given data then
|
|
the ioctl will return -EINVAL.
|
|
|
|
4.92 KVM_S390_IRQ
|
|
-----------------
|
|
|
|
:Capability: KVM_CAP_S390_INJECT_IRQ
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_s390_irq (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
|
|
====== =================================================================
|
|
EINVAL interrupt type is invalid
|
|
type is KVM_S390_SIGP_STOP and flag parameter is invalid value,
|
|
type is KVM_S390_INT_EXTERNAL_CALL and code is bigger
|
|
than the maximum of VCPUs
|
|
EBUSY type is KVM_S390_SIGP_SET_PREFIX and vcpu is not stopped,
|
|
type is KVM_S390_SIGP_STOP and a stop irq is already pending,
|
|
type is KVM_S390_INT_EXTERNAL_CALL and an external call interrupt
|
|
is already pending
|
|
====== =================================================================
|
|
|
|
Allows to inject an interrupt to the guest.
|
|
|
|
Using struct kvm_s390_irq as a parameter allows
|
|
to inject additional payload which is not
|
|
possible via KVM_S390_INTERRUPT.
|
|
|
|
Interrupt parameters are passed via kvm_s390_irq::
|
|
|
|
struct kvm_s390_irq {
|
|
__u64 type;
|
|
union {
|
|
struct kvm_s390_io_info io;
|
|
struct kvm_s390_ext_info ext;
|
|
struct kvm_s390_pgm_info pgm;
|
|
struct kvm_s390_emerg_info emerg;
|
|
struct kvm_s390_extcall_info extcall;
|
|
struct kvm_s390_prefix_info prefix;
|
|
struct kvm_s390_stop_info stop;
|
|
struct kvm_s390_mchk_info mchk;
|
|
char reserved[64];
|
|
} u;
|
|
};
|
|
|
|
type can be one of the following:
|
|
|
|
- KVM_S390_SIGP_STOP - sigp stop; parameter in .stop
|
|
- KVM_S390_PROGRAM_INT - program check; parameters in .pgm
|
|
- KVM_S390_SIGP_SET_PREFIX - sigp set prefix; parameters in .prefix
|
|
- KVM_S390_RESTART - restart; no parameters
|
|
- KVM_S390_INT_CLOCK_COMP - clock comparator interrupt; no parameters
|
|
- KVM_S390_INT_CPU_TIMER - CPU timer interrupt; no parameters
|
|
- KVM_S390_INT_EMERGENCY - sigp emergency; parameters in .emerg
|
|
- KVM_S390_INT_EXTERNAL_CALL - sigp external call; parameters in .extcall
|
|
- KVM_S390_MCHK - machine check interrupt; parameters in .mchk
|
|
|
|
This is an asynchronous vcpu ioctl and can be invoked from any thread.
|
|
|
|
4.94 KVM_S390_GET_IRQ_STATE
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_S390_IRQ_STATE
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_s390_irq_state (out)
|
|
:Returns: >= number of bytes copied into buffer,
|
|
-EINVAL if buffer size is 0,
|
|
-ENOBUFS if buffer size is too small to fit all pending interrupts,
|
|
-EFAULT if the buffer address was invalid
|
|
|
|
This ioctl allows userspace to retrieve the complete state of all currently
|
|
pending interrupts in a single buffer. Use cases include migration
|
|
and introspection. The parameter structure contains the address of a
|
|
userspace buffer and its length::
|
|
|
|
struct kvm_s390_irq_state {
|
|
__u64 buf;
|
|
__u32 flags; /* will stay unused for compatibility reasons */
|
|
__u32 len;
|
|
__u32 reserved[4]; /* will stay unused for compatibility reasons */
|
|
};
|
|
|
|
Userspace passes in the above struct and for each pending interrupt a
|
|
struct kvm_s390_irq is copied to the provided buffer.
|
|
|
|
The structure contains a flags and a reserved field for future extensions. As
|
|
the kernel never checked for flags == 0 and QEMU never pre-zeroed flags and
|
|
reserved, these fields can not be used in the future without breaking
|
|
compatibility.
|
|
|
|
If -ENOBUFS is returned the buffer provided was too small and userspace
|
|
may retry with a bigger buffer.
|
|
|
|
4.95 KVM_S390_SET_IRQ_STATE
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_S390_IRQ_STATE
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_s390_irq_state (in)
|
|
:Returns: 0 on success,
|
|
-EFAULT if the buffer address was invalid,
|
|
-EINVAL for an invalid buffer length (see below),
|
|
-EBUSY if there were already interrupts pending,
|
|
errors occurring when actually injecting the
|
|
interrupt. See KVM_S390_IRQ.
|
|
|
|
This ioctl allows userspace to set the complete state of all cpu-local
|
|
interrupts currently pending for the vcpu. It is intended for restoring
|
|
interrupt state after a migration. The input parameter is a userspace buffer
|
|
containing a struct kvm_s390_irq_state::
|
|
|
|
struct kvm_s390_irq_state {
|
|
__u64 buf;
|
|
__u32 flags; /* will stay unused for compatibility reasons */
|
|
__u32 len;
|
|
__u32 reserved[4]; /* will stay unused for compatibility reasons */
|
|
};
|
|
|
|
The restrictions for flags and reserved apply as well.
|
|
(see KVM_S390_GET_IRQ_STATE)
|
|
|
|
The userspace memory referenced by buf contains a struct kvm_s390_irq
|
|
for each interrupt to be injected into the guest.
|
|
If one of the interrupts could not be injected for some reason the
|
|
ioctl aborts.
|
|
|
|
len must be a multiple of sizeof(struct kvm_s390_irq). It must be > 0
|
|
and it must not exceed (max_vcpus + 32) * sizeof(struct kvm_s390_irq),
|
|
which is the maximum number of possibly pending cpu-local interrupts.
|
|
|
|
4.96 KVM_SMI
|
|
------------
|
|
|
|
:Capability: KVM_CAP_X86_SMM
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Queues an SMI on the thread's vcpu.
|
|
|
|
4.97 KVM_X86_SET_MSR_FILTER
|
|
----------------------------
|
|
|
|
:Capability: KVM_X86_SET_MSR_FILTER
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_msr_filter
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
::
|
|
|
|
struct kvm_msr_filter_range {
|
|
#define KVM_MSR_FILTER_READ (1 << 0)
|
|
#define KVM_MSR_FILTER_WRITE (1 << 1)
|
|
__u32 flags;
|
|
__u32 nmsrs; /* number of msrs in bitmap */
|
|
__u32 base; /* MSR index the bitmap starts at */
|
|
__u8 *bitmap; /* a 1 bit allows the operations in flags, 0 denies */
|
|
};
|
|
|
|
#define KVM_MSR_FILTER_MAX_RANGES 16
|
|
struct kvm_msr_filter {
|
|
#define KVM_MSR_FILTER_DEFAULT_ALLOW (0 << 0)
|
|
#define KVM_MSR_FILTER_DEFAULT_DENY (1 << 0)
|
|
__u32 flags;
|
|
struct kvm_msr_filter_range ranges[KVM_MSR_FILTER_MAX_RANGES];
|
|
};
|
|
|
|
flags values for ``struct kvm_msr_filter_range``:
|
|
|
|
``KVM_MSR_FILTER_READ``
|
|
|
|
Filter read accesses to MSRs using the given bitmap. A 0 in the bitmap
|
|
indicates that a read should immediately fail, while a 1 indicates that
|
|
a read for a particular MSR should be handled regardless of the default
|
|
filter action.
|
|
|
|
``KVM_MSR_FILTER_WRITE``
|
|
|
|
Filter write accesses to MSRs using the given bitmap. A 0 in the bitmap
|
|
indicates that a write should immediately fail, while a 1 indicates that
|
|
a write for a particular MSR should be handled regardless of the default
|
|
filter action.
|
|
|
|
``KVM_MSR_FILTER_READ | KVM_MSR_FILTER_WRITE``
|
|
|
|
Filter both read and write accesses to MSRs using the given bitmap. A 0
|
|
in the bitmap indicates that both reads and writes should immediately fail,
|
|
while a 1 indicates that reads and writes for a particular MSR are not
|
|
filtered by this range.
|
|
|
|
flags values for ``struct kvm_msr_filter``:
|
|
|
|
``KVM_MSR_FILTER_DEFAULT_ALLOW``
|
|
|
|
If no filter range matches an MSR index that is getting accessed, KVM will
|
|
fall back to allowing access to the MSR.
|
|
|
|
``KVM_MSR_FILTER_DEFAULT_DENY``
|
|
|
|
If no filter range matches an MSR index that is getting accessed, KVM will
|
|
fall back to rejecting access to the MSR. In this mode, all MSRs that should
|
|
be processed by KVM need to explicitly be marked as allowed in the bitmaps.
|
|
|
|
This ioctl allows user space to define up to 16 bitmaps of MSR ranges to
|
|
specify whether a certain MSR access should be explicitly filtered for or not.
|
|
|
|
If this ioctl has never been invoked, MSR accesses are not guarded and the
|
|
default KVM in-kernel emulation behavior is fully preserved.
|
|
|
|
Calling this ioctl with an empty set of ranges (all nmsrs == 0) disables MSR
|
|
filtering. In that mode, ``KVM_MSR_FILTER_DEFAULT_DENY`` is invalid and causes
|
|
an error.
|
|
|
|
As soon as the filtering is in place, every MSR access is processed through
|
|
the filtering except for accesses to the x2APIC MSRs (from 0x800 to 0x8ff);
|
|
x2APIC MSRs are always allowed, independent of the ``default_allow`` setting,
|
|
and their behavior depends on the ``X2APIC_ENABLE`` bit of the APIC base
|
|
register.
|
|
|
|
.. warning::
|
|
MSR accesses coming from nested vmentry/vmexit are not filtered.
|
|
This includes both writes to individual VMCS fields and reads/writes
|
|
through the MSR lists pointed to by the VMCS.
|
|
|
|
If a bit is within one of the defined ranges, read and write accesses are
|
|
guarded by the bitmap's value for the MSR index if the kind of access
|
|
is included in the ``struct kvm_msr_filter_range`` flags. If no range
|
|
cover this particular access, the behavior is determined by the flags
|
|
field in the kvm_msr_filter struct: ``KVM_MSR_FILTER_DEFAULT_ALLOW``
|
|
and ``KVM_MSR_FILTER_DEFAULT_DENY``.
|
|
|
|
Each bitmap range specifies a range of MSRs to potentially allow access on.
|
|
The range goes from MSR index [base .. base+nmsrs]. The flags field
|
|
indicates whether reads, writes or both reads and writes are filtered
|
|
by setting a 1 bit in the bitmap for the corresponding MSR index.
|
|
|
|
If an MSR access is not permitted through the filtering, it generates a
|
|
#GP inside the guest. When combined with KVM_CAP_X86_USER_SPACE_MSR, that
|
|
allows user space to deflect and potentially handle various MSR accesses
|
|
into user space.
|
|
|
|
If a vCPU is in running state while this ioctl is invoked, the vCPU may
|
|
experience inconsistent filtering behavior on MSR accesses.
|
|
|
|
4.98 KVM_CREATE_SPAPR_TCE_64
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_SPAPR_TCE_64
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_create_spapr_tce_64 (in)
|
|
:Returns: file descriptor for manipulating the created TCE table
|
|
|
|
This is an extension for KVM_CAP_SPAPR_TCE which only supports 32bit
|
|
windows, described in 4.62 KVM_CREATE_SPAPR_TCE
|
|
|
|
This capability uses extended struct in ioctl interface::
|
|
|
|
/* for KVM_CAP_SPAPR_TCE_64 */
|
|
struct kvm_create_spapr_tce_64 {
|
|
__u64 liobn;
|
|
__u32 page_shift;
|
|
__u32 flags;
|
|
__u64 offset; /* in pages */
|
|
__u64 size; /* in pages */
|
|
};
|
|
|
|
The aim of extension is to support an additional bigger DMA window with
|
|
a variable page size.
|
|
KVM_CREATE_SPAPR_TCE_64 receives a 64bit window size, an IOMMU page shift and
|
|
a bus offset of the corresponding DMA window, @size and @offset are numbers
|
|
of IOMMU pages.
|
|
|
|
@flags are not used at the moment.
|
|
|
|
The rest of functionality is identical to KVM_CREATE_SPAPR_TCE.
|
|
|
|
4.99 KVM_REINJECT_CONTROL
|
|
-------------------------
|
|
|
|
:Capability: KVM_CAP_REINJECT_CONTROL
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_reinject_control (in)
|
|
:Returns: 0 on success,
|
|
-EFAULT if struct kvm_reinject_control cannot be read,
|
|
-ENXIO if KVM_CREATE_PIT or KVM_CREATE_PIT2 didn't succeed earlier.
|
|
|
|
i8254 (PIT) has two modes, reinject and !reinject. The default is reinject,
|
|
where KVM queues elapsed i8254 ticks and monitors completion of interrupt from
|
|
vector(s) that i8254 injects. Reinject mode dequeues a tick and injects its
|
|
interrupt whenever there isn't a pending interrupt from i8254.
|
|
!reinject mode injects an interrupt as soon as a tick arrives.
|
|
|
|
::
|
|
|
|
struct kvm_reinject_control {
|
|
__u8 pit_reinject;
|
|
__u8 reserved[31];
|
|
};
|
|
|
|
pit_reinject = 0 (!reinject mode) is recommended, unless running an old
|
|
operating system that uses the PIT for timing (e.g. Linux 2.4.x).
|
|
|
|
4.100 KVM_PPC_CONFIGURE_V3_MMU
|
|
------------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_RADIX_MMU or KVM_CAP_PPC_HASH_MMU_V3
|
|
:Architectures: ppc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_mmuv3_cfg (in)
|
|
:Returns: 0 on success,
|
|
-EFAULT if struct kvm_ppc_mmuv3_cfg cannot be read,
|
|
-EINVAL if the configuration is invalid
|
|
|
|
This ioctl controls whether the guest will use radix or HPT (hashed
|
|
page table) translation, and sets the pointer to the process table for
|
|
the guest.
|
|
|
|
::
|
|
|
|
struct kvm_ppc_mmuv3_cfg {
|
|
__u64 flags;
|
|
__u64 process_table;
|
|
};
|
|
|
|
There are two bits that can be set in flags; KVM_PPC_MMUV3_RADIX and
|
|
KVM_PPC_MMUV3_GTSE. KVM_PPC_MMUV3_RADIX, if set, configures the guest
|
|
to use radix tree translation, and if clear, to use HPT translation.
|
|
KVM_PPC_MMUV3_GTSE, if set and if KVM permits it, configures the guest
|
|
to be able to use the global TLB and SLB invalidation instructions;
|
|
if clear, the guest may not use these instructions.
|
|
|
|
The process_table field specifies the address and size of the guest
|
|
process table, which is in the guest's space. This field is formatted
|
|
as the second doubleword of the partition table entry, as defined in
|
|
the Power ISA V3.00, Book III section 5.7.6.1.
|
|
|
|
4.101 KVM_PPC_GET_RMMU_INFO
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_RADIX_MMU
|
|
:Architectures: ppc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_rmmu_info (out)
|
|
:Returns: 0 on success,
|
|
-EFAULT if struct kvm_ppc_rmmu_info cannot be written,
|
|
-EINVAL if no useful information can be returned
|
|
|
|
This ioctl returns a structure containing two things: (a) a list
|
|
containing supported radix tree geometries, and (b) a list that maps
|
|
page sizes to put in the "AP" (actual page size) field for the tlbie
|
|
(TLB invalidate entry) instruction.
|
|
|
|
::
|
|
|
|
struct kvm_ppc_rmmu_info {
|
|
struct kvm_ppc_radix_geom {
|
|
__u8 page_shift;
|
|
__u8 level_bits[4];
|
|
__u8 pad[3];
|
|
} geometries[8];
|
|
__u32 ap_encodings[8];
|
|
};
|
|
|
|
The geometries[] field gives up to 8 supported geometries for the
|
|
radix page table, in terms of the log base 2 of the smallest page
|
|
size, and the number of bits indexed at each level of the tree, from
|
|
the PTE level up to the PGD level in that order. Any unused entries
|
|
will have 0 in the page_shift field.
|
|
|
|
The ap_encodings gives the supported page sizes and their AP field
|
|
encodings, encoded with the AP value in the top 3 bits and the log
|
|
base 2 of the page size in the bottom 6 bits.
|
|
|
|
4.102 KVM_PPC_RESIZE_HPT_PREPARE
|
|
--------------------------------
|
|
|
|
:Capability: KVM_CAP_SPAPR_RESIZE_HPT
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_resize_hpt (in)
|
|
:Returns: 0 on successful completion,
|
|
>0 if a new HPT is being prepared, the value is an estimated
|
|
number of milliseconds until preparation is complete,
|
|
-EFAULT if struct kvm_reinject_control cannot be read,
|
|
-EINVAL if the supplied shift or flags are invalid,
|
|
-ENOMEM if unable to allocate the new HPT,
|
|
|
|
Used to implement the PAPR extension for runtime resizing of a guest's
|
|
Hashed Page Table (HPT). Specifically this starts, stops or monitors
|
|
the preparation of a new potential HPT for the guest, essentially
|
|
implementing the H_RESIZE_HPT_PREPARE hypercall.
|
|
|
|
::
|
|
|
|
struct kvm_ppc_resize_hpt {
|
|
__u64 flags;
|
|
__u32 shift;
|
|
__u32 pad;
|
|
};
|
|
|
|
If called with shift > 0 when there is no pending HPT for the guest,
|
|
this begins preparation of a new pending HPT of size 2^(shift) bytes.
|
|
It then returns a positive integer with the estimated number of
|
|
milliseconds until preparation is complete.
|
|
|
|
If called when there is a pending HPT whose size does not match that
|
|
requested in the parameters, discards the existing pending HPT and
|
|
creates a new one as above.
|
|
|
|
If called when there is a pending HPT of the size requested, will:
|
|
|
|
* If preparation of the pending HPT is already complete, return 0
|
|
* If preparation of the pending HPT has failed, return an error
|
|
code, then discard the pending HPT.
|
|
* If preparation of the pending HPT is still in progress, return an
|
|
estimated number of milliseconds until preparation is complete.
|
|
|
|
If called with shift == 0, discards any currently pending HPT and
|
|
returns 0 (i.e. cancels any in-progress preparation).
|
|
|
|
flags is reserved for future expansion, currently setting any bits in
|
|
flags will result in an -EINVAL.
|
|
|
|
Normally this will be called repeatedly with the same parameters until
|
|
it returns <= 0. The first call will initiate preparation, subsequent
|
|
ones will monitor preparation until it completes or fails.
|
|
|
|
4.103 KVM_PPC_RESIZE_HPT_COMMIT
|
|
-------------------------------
|
|
|
|
:Capability: KVM_CAP_SPAPR_RESIZE_HPT
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_resize_hpt (in)
|
|
:Returns: 0 on successful completion,
|
|
-EFAULT if struct kvm_reinject_control cannot be read,
|
|
-EINVAL if the supplied shift or flags are invalid,
|
|
-ENXIO is there is no pending HPT, or the pending HPT doesn't
|
|
have the requested size,
|
|
-EBUSY if the pending HPT is not fully prepared,
|
|
-ENOSPC if there was a hash collision when moving existing
|
|
HPT entries to the new HPT,
|
|
-EIO on other error conditions
|
|
|
|
Used to implement the PAPR extension for runtime resizing of a guest's
|
|
Hashed Page Table (HPT). Specifically this requests that the guest be
|
|
transferred to working with the new HPT, essentially implementing the
|
|
H_RESIZE_HPT_COMMIT hypercall.
|
|
|
|
::
|
|
|
|
struct kvm_ppc_resize_hpt {
|
|
__u64 flags;
|
|
__u32 shift;
|
|
__u32 pad;
|
|
};
|
|
|
|
This should only be called after KVM_PPC_RESIZE_HPT_PREPARE has
|
|
returned 0 with the same parameters. In other cases
|
|
KVM_PPC_RESIZE_HPT_COMMIT will return an error (usually -ENXIO or
|
|
-EBUSY, though others may be possible if the preparation was started,
|
|
but failed).
|
|
|
|
This will have undefined effects on the guest if it has not already
|
|
placed itself in a quiescent state where no vcpu will make MMU enabled
|
|
memory accesses.
|
|
|
|
On succsful completion, the pending HPT will become the guest's active
|
|
HPT and the previous HPT will be discarded.
|
|
|
|
On failure, the guest will still be operating on its previous HPT.
|
|
|
|
4.104 KVM_X86_GET_MCE_CAP_SUPPORTED
|
|
-----------------------------------
|
|
|
|
:Capability: KVM_CAP_MCE
|
|
:Architectures: x86
|
|
:Type: system ioctl
|
|
:Parameters: u64 mce_cap (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Returns supported MCE capabilities. The u64 mce_cap parameter
|
|
has the same format as the MSR_IA32_MCG_CAP register. Supported
|
|
capabilities will have the corresponding bits set.
|
|
|
|
4.105 KVM_X86_SETUP_MCE
|
|
-----------------------
|
|
|
|
:Capability: KVM_CAP_MCE
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: u64 mcg_cap (in)
|
|
:Returns: 0 on success,
|
|
-EFAULT if u64 mcg_cap cannot be read,
|
|
-EINVAL if the requested number of banks is invalid,
|
|
-EINVAL if requested MCE capability is not supported.
|
|
|
|
Initializes MCE support for use. The u64 mcg_cap parameter
|
|
has the same format as the MSR_IA32_MCG_CAP register and
|
|
specifies which capabilities should be enabled. The maximum
|
|
supported number of error-reporting banks can be retrieved when
|
|
checking for KVM_CAP_MCE. The supported capabilities can be
|
|
retrieved with KVM_X86_GET_MCE_CAP_SUPPORTED.
|
|
|
|
4.106 KVM_X86_SET_MCE
|
|
---------------------
|
|
|
|
:Capability: KVM_CAP_MCE
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_x86_mce (in)
|
|
:Returns: 0 on success,
|
|
-EFAULT if struct kvm_x86_mce cannot be read,
|
|
-EINVAL if the bank number is invalid,
|
|
-EINVAL if VAL bit is not set in status field.
|
|
|
|
Inject a machine check error (MCE) into the guest. The input
|
|
parameter is::
|
|
|
|
struct kvm_x86_mce {
|
|
__u64 status;
|
|
__u64 addr;
|
|
__u64 misc;
|
|
__u64 mcg_status;
|
|
__u8 bank;
|
|
__u8 pad1[7];
|
|
__u64 pad2[3];
|
|
};
|
|
|
|
If the MCE being reported is an uncorrected error, KVM will
|
|
inject it as an MCE exception into the guest. If the guest
|
|
MCG_STATUS register reports that an MCE is in progress, KVM
|
|
causes an KVM_EXIT_SHUTDOWN vmexit.
|
|
|
|
Otherwise, if the MCE is a corrected error, KVM will just
|
|
store it in the corresponding bank (provided this bank is
|
|
not holding a previously reported uncorrected error).
|
|
|
|
4.107 KVM_S390_GET_CMMA_BITS
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_S390_CMMA_MIGRATION
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_s390_cmma_log (in, out)
|
|
:Returns: 0 on success, a negative value on error
|
|
|
|
This ioctl is used to get the values of the CMMA bits on the s390
|
|
architecture. It is meant to be used in two scenarios:
|
|
|
|
- During live migration to save the CMMA values. Live migration needs
|
|
to be enabled via the KVM_REQ_START_MIGRATION VM property.
|
|
- To non-destructively peek at the CMMA values, with the flag
|
|
KVM_S390_CMMA_PEEK set.
|
|
|
|
The ioctl takes parameters via the kvm_s390_cmma_log struct. The desired
|
|
values are written to a buffer whose location is indicated via the "values"
|
|
member in the kvm_s390_cmma_log struct. The values in the input struct are
|
|
also updated as needed.
|
|
|
|
Each CMMA value takes up one byte.
|
|
|
|
::
|
|
|
|
struct kvm_s390_cmma_log {
|
|
__u64 start_gfn;
|
|
__u32 count;
|
|
__u32 flags;
|
|
union {
|
|
__u64 remaining;
|
|
__u64 mask;
|
|
};
|
|
__u64 values;
|
|
};
|
|
|
|
start_gfn is the number of the first guest frame whose CMMA values are
|
|
to be retrieved,
|
|
|
|
count is the length of the buffer in bytes,
|
|
|
|
values points to the buffer where the result will be written to.
|
|
|
|
If count is greater than KVM_S390_SKEYS_MAX, then it is considered to be
|
|
KVM_S390_SKEYS_MAX. KVM_S390_SKEYS_MAX is re-used for consistency with
|
|
other ioctls.
|
|
|
|
The result is written in the buffer pointed to by the field values, and
|
|
the values of the input parameter are updated as follows.
|
|
|
|
Depending on the flags, different actions are performed. The only
|
|
supported flag so far is KVM_S390_CMMA_PEEK.
|
|
|
|
The default behaviour if KVM_S390_CMMA_PEEK is not set is:
|
|
start_gfn will indicate the first page frame whose CMMA bits were dirty.
|
|
It is not necessarily the same as the one passed as input, as clean pages
|
|
are skipped.
|
|
|
|
count will indicate the number of bytes actually written in the buffer.
|
|
It can (and very often will) be smaller than the input value, since the
|
|
buffer is only filled until 16 bytes of clean values are found (which
|
|
are then not copied in the buffer). Since a CMMA migration block needs
|
|
the base address and the length, for a total of 16 bytes, we will send
|
|
back some clean data if there is some dirty data afterwards, as long as
|
|
the size of the clean data does not exceed the size of the header. This
|
|
allows to minimize the amount of data to be saved or transferred over
|
|
the network at the expense of more roundtrips to userspace. The next
|
|
invocation of the ioctl will skip over all the clean values, saving
|
|
potentially more than just the 16 bytes we found.
|
|
|
|
If KVM_S390_CMMA_PEEK is set:
|
|
the existing storage attributes are read even when not in migration
|
|
mode, and no other action is performed;
|
|
|
|
the output start_gfn will be equal to the input start_gfn,
|
|
|
|
the output count will be equal to the input count, except if the end of
|
|
memory has been reached.
|
|
|
|
In both cases:
|
|
the field "remaining" will indicate the total number of dirty CMMA values
|
|
still remaining, or 0 if KVM_S390_CMMA_PEEK is set and migration mode is
|
|
not enabled.
|
|
|
|
mask is unused.
|
|
|
|
values points to the userspace buffer where the result will be stored.
|
|
|
|
This ioctl can fail with -ENOMEM if not enough memory can be allocated to
|
|
complete the task, with -ENXIO if CMMA is not enabled, with -EINVAL if
|
|
KVM_S390_CMMA_PEEK is not set but migration mode was not enabled, with
|
|
-EFAULT if the userspace address is invalid or if no page table is
|
|
present for the addresses (e.g. when using hugepages).
|
|
|
|
4.108 KVM_S390_SET_CMMA_BITS
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_S390_CMMA_MIGRATION
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_s390_cmma_log (in)
|
|
:Returns: 0 on success, a negative value on error
|
|
|
|
This ioctl is used to set the values of the CMMA bits on the s390
|
|
architecture. It is meant to be used during live migration to restore
|
|
the CMMA values, but there are no restrictions on its use.
|
|
The ioctl takes parameters via the kvm_s390_cmma_values struct.
|
|
Each CMMA value takes up one byte.
|
|
|
|
::
|
|
|
|
struct kvm_s390_cmma_log {
|
|
__u64 start_gfn;
|
|
__u32 count;
|
|
__u32 flags;
|
|
union {
|
|
__u64 remaining;
|
|
__u64 mask;
|
|
};
|
|
__u64 values;
|
|
};
|
|
|
|
start_gfn indicates the starting guest frame number,
|
|
|
|
count indicates how many values are to be considered in the buffer,
|
|
|
|
flags is not used and must be 0.
|
|
|
|
mask indicates which PGSTE bits are to be considered.
|
|
|
|
remaining is not used.
|
|
|
|
values points to the buffer in userspace where to store the values.
|
|
|
|
This ioctl can fail with -ENOMEM if not enough memory can be allocated to
|
|
complete the task, with -ENXIO if CMMA is not enabled, with -EINVAL if
|
|
the count field is too large (e.g. more than KVM_S390_CMMA_SIZE_MAX) or
|
|
if the flags field was not 0, with -EFAULT if the userspace address is
|
|
invalid, if invalid pages are written to (e.g. after the end of memory)
|
|
or if no page table is present for the addresses (e.g. when using
|
|
hugepages).
|
|
|
|
4.109 KVM_PPC_GET_CPU_CHAR
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_GET_CPU_CHAR
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_ppc_cpu_char (out)
|
|
:Returns: 0 on successful completion,
|
|
-EFAULT if struct kvm_ppc_cpu_char cannot be written
|
|
|
|
This ioctl gives userspace information about certain characteristics
|
|
of the CPU relating to speculative execution of instructions and
|
|
possible information leakage resulting from speculative execution (see
|
|
CVE-2017-5715, CVE-2017-5753 and CVE-2017-5754). The information is
|
|
returned in struct kvm_ppc_cpu_char, which looks like this::
|
|
|
|
struct kvm_ppc_cpu_char {
|
|
__u64 character; /* characteristics of the CPU */
|
|
__u64 behaviour; /* recommended software behaviour */
|
|
__u64 character_mask; /* valid bits in character */
|
|
__u64 behaviour_mask; /* valid bits in behaviour */
|
|
};
|
|
|
|
For extensibility, the character_mask and behaviour_mask fields
|
|
indicate which bits of character and behaviour have been filled in by
|
|
the kernel. If the set of defined bits is extended in future then
|
|
userspace will be able to tell whether it is running on a kernel that
|
|
knows about the new bits.
|
|
|
|
The character field describes attributes of the CPU which can help
|
|
with preventing inadvertent information disclosure - specifically,
|
|
whether there is an instruction to flash-invalidate the L1 data cache
|
|
(ori 30,30,0 or mtspr SPRN_TRIG2,rN), whether the L1 data cache is set
|
|
to a mode where entries can only be used by the thread that created
|
|
them, whether the bcctr[l] instruction prevents speculation, and
|
|
whether a speculation barrier instruction (ori 31,31,0) is provided.
|
|
|
|
The behaviour field describes actions that software should take to
|
|
prevent inadvertent information disclosure, and thus describes which
|
|
vulnerabilities the hardware is subject to; specifically whether the
|
|
L1 data cache should be flushed when returning to user mode from the
|
|
kernel, and whether a speculation barrier should be placed between an
|
|
array bounds check and the array access.
|
|
|
|
These fields use the same bit definitions as the new
|
|
H_GET_CPU_CHARACTERISTICS hypercall.
|
|
|
|
4.110 KVM_MEMORY_ENCRYPT_OP
|
|
---------------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: vm
|
|
:Parameters: an opaque platform specific structure (in/out)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
If the platform supports creating encrypted VMs then this ioctl can be used
|
|
for issuing platform-specific memory encryption commands to manage those
|
|
encrypted VMs.
|
|
|
|
Currently, this ioctl is used for issuing Secure Encrypted Virtualization
|
|
(SEV) commands on AMD Processors. The SEV commands are defined in
|
|
Documentation/virt/kvm/x86/amd-memory-encryption.rst.
|
|
|
|
4.111 KVM_MEMORY_ENCRYPT_REG_REGION
|
|
-----------------------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: system
|
|
:Parameters: struct kvm_enc_region (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This ioctl can be used to register a guest memory region which may
|
|
contain encrypted data (e.g. guest RAM, SMRAM etc).
|
|
|
|
It is used in the SEV-enabled guest. When encryption is enabled, a guest
|
|
memory region may contain encrypted data. The SEV memory encryption
|
|
engine uses a tweak such that two identical plaintext pages, each at
|
|
different locations will have differing ciphertexts. So swapping or
|
|
moving ciphertext of those pages will not result in plaintext being
|
|
swapped. So relocating (or migrating) physical backing pages for the SEV
|
|
guest will require some additional steps.
|
|
|
|
Note: The current SEV key management spec does not provide commands to
|
|
swap or migrate (move) ciphertext pages. Hence, for now we pin the guest
|
|
memory region registered with the ioctl.
|
|
|
|
4.112 KVM_MEMORY_ENCRYPT_UNREG_REGION
|
|
-------------------------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: x86
|
|
:Type: system
|
|
:Parameters: struct kvm_enc_region (in)
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This ioctl can be used to unregister the guest memory region registered
|
|
with KVM_MEMORY_ENCRYPT_REG_REGION ioctl above.
|
|
|
|
4.113 KVM_HYPERV_EVENTFD
|
|
------------------------
|
|
|
|
:Capability: KVM_CAP_HYPERV_EVENTFD
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_hyperv_eventfd (in)
|
|
|
|
This ioctl (un)registers an eventfd to receive notifications from the guest on
|
|
the specified Hyper-V connection id through the SIGNAL_EVENT hypercall, without
|
|
causing a user exit. SIGNAL_EVENT hypercall with non-zero event flag number
|
|
(bits 24-31) still triggers a KVM_EXIT_HYPERV_HCALL user exit.
|
|
|
|
::
|
|
|
|
struct kvm_hyperv_eventfd {
|
|
__u32 conn_id;
|
|
__s32 fd;
|
|
__u32 flags;
|
|
__u32 padding[3];
|
|
};
|
|
|
|
The conn_id field should fit within 24 bits::
|
|
|
|
#define KVM_HYPERV_CONN_ID_MASK 0x00ffffff
|
|
|
|
The acceptable values for the flags field are::
|
|
|
|
#define KVM_HYPERV_EVENTFD_DEASSIGN (1 << 0)
|
|
|
|
:Returns: 0 on success,
|
|
-EINVAL if conn_id or flags is outside the allowed range,
|
|
-ENOENT on deassign if the conn_id isn't registered,
|
|
-EEXIST on assign if the conn_id is already registered
|
|
|
|
4.114 KVM_GET_NESTED_STATE
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_NESTED_STATE
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_nested_state (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
===== =============================================================
|
|
E2BIG the total state size exceeds the value of 'size' specified by
|
|
the user; the size required will be written into size.
|
|
===== =============================================================
|
|
|
|
::
|
|
|
|
struct kvm_nested_state {
|
|
__u16 flags;
|
|
__u16 format;
|
|
__u32 size;
|
|
|
|
union {
|
|
struct kvm_vmx_nested_state_hdr vmx;
|
|
struct kvm_svm_nested_state_hdr svm;
|
|
|
|
/* Pad the header to 128 bytes. */
|
|
__u8 pad[120];
|
|
} hdr;
|
|
|
|
union {
|
|
struct kvm_vmx_nested_state_data vmx[0];
|
|
struct kvm_svm_nested_state_data svm[0];
|
|
} data;
|
|
};
|
|
|
|
#define KVM_STATE_NESTED_GUEST_MODE 0x00000001
|
|
#define KVM_STATE_NESTED_RUN_PENDING 0x00000002
|
|
#define KVM_STATE_NESTED_EVMCS 0x00000004
|
|
|
|
#define KVM_STATE_NESTED_FORMAT_VMX 0
|
|
#define KVM_STATE_NESTED_FORMAT_SVM 1
|
|
|
|
#define KVM_STATE_NESTED_VMX_VMCS_SIZE 0x1000
|
|
|
|
#define KVM_STATE_NESTED_VMX_SMM_GUEST_MODE 0x00000001
|
|
#define KVM_STATE_NESTED_VMX_SMM_VMXON 0x00000002
|
|
|
|
#define KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE 0x00000001
|
|
|
|
struct kvm_vmx_nested_state_hdr {
|
|
__u64 vmxon_pa;
|
|
__u64 vmcs12_pa;
|
|
|
|
struct {
|
|
__u16 flags;
|
|
} smm;
|
|
|
|
__u32 flags;
|
|
__u64 preemption_timer_deadline;
|
|
};
|
|
|
|
struct kvm_vmx_nested_state_data {
|
|
__u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
|
|
__u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
|
|
};
|
|
|
|
This ioctl copies the vcpu's nested virtualization state from the kernel to
|
|
userspace.
|
|
|
|
The maximum size of the state can be retrieved by passing KVM_CAP_NESTED_STATE
|
|
to the KVM_CHECK_EXTENSION ioctl().
|
|
|
|
4.115 KVM_SET_NESTED_STATE
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_NESTED_STATE
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_nested_state (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
This copies the vcpu's kvm_nested_state struct from userspace to the kernel.
|
|
For the definition of struct kvm_nested_state, see KVM_GET_NESTED_STATE.
|
|
|
|
4.116 KVM_(UN)REGISTER_COALESCED_MMIO
|
|
-------------------------------------
|
|
|
|
:Capability: KVM_CAP_COALESCED_MMIO (for coalesced mmio)
|
|
KVM_CAP_COALESCED_PIO (for coalesced pio)
|
|
:Architectures: all
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_coalesced_mmio_zone
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
Coalesced I/O is a performance optimization that defers hardware
|
|
register write emulation so that userspace exits are avoided. It is
|
|
typically used to reduce the overhead of emulating frequently accessed
|
|
hardware registers.
|
|
|
|
When a hardware register is configured for coalesced I/O, write accesses
|
|
do not exit to userspace and their value is recorded in a ring buffer
|
|
that is shared between kernel and userspace.
|
|
|
|
Coalesced I/O is used if one or more write accesses to a hardware
|
|
register can be deferred until a read or a write to another hardware
|
|
register on the same device. This last access will cause a vmexit and
|
|
userspace will process accesses from the ring buffer before emulating
|
|
it. That will avoid exiting to userspace on repeated writes.
|
|
|
|
Coalesced pio is based on coalesced mmio. There is little difference
|
|
between coalesced mmio and pio except that coalesced pio records accesses
|
|
to I/O ports.
|
|
|
|
4.117 KVM_CLEAR_DIRTY_LOG (vm ioctl)
|
|
------------------------------------
|
|
|
|
:Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
|
|
:Architectures: x86, arm64, mips
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_clear_dirty_log (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
/* for KVM_CLEAR_DIRTY_LOG */
|
|
struct kvm_clear_dirty_log {
|
|
__u32 slot;
|
|
__u32 num_pages;
|
|
__u64 first_page;
|
|
union {
|
|
void __user *dirty_bitmap; /* one bit per page */
|
|
__u64 padding;
|
|
};
|
|
};
|
|
|
|
The ioctl clears the dirty status of pages in a memory slot, according to
|
|
the bitmap that is passed in struct kvm_clear_dirty_log's dirty_bitmap
|
|
field. Bit 0 of the bitmap corresponds to page "first_page" in the
|
|
memory slot, and num_pages is the size in bits of the input bitmap.
|
|
first_page must be a multiple of 64; num_pages must also be a multiple of
|
|
64 unless first_page + num_pages is the size of the memory slot. For each
|
|
bit that is set in the input bitmap, the corresponding page is marked "clean"
|
|
in KVM's dirty bitmap, and dirty tracking is re-enabled for that page
|
|
(for example via write-protection, or by clearing the dirty bit in
|
|
a page table entry).
|
|
|
|
If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of slot field specifies
|
|
the address space for which you want to clear the dirty status. See
|
|
KVM_SET_USER_MEMORY_REGION for details on the usage of slot field.
|
|
|
|
This ioctl is mostly useful when KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
|
|
is enabled; for more information, see the description of the capability.
|
|
However, it can always be used as long as KVM_CHECK_EXTENSION confirms
|
|
that KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is present.
|
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|
|
4.118 KVM_GET_SUPPORTED_HV_CPUID
|
|
--------------------------------
|
|
|
|
:Capability: KVM_CAP_HYPERV_CPUID (vcpu), KVM_CAP_SYS_HYPERV_CPUID (system)
|
|
:Architectures: x86
|
|
:Type: system ioctl, vcpu ioctl
|
|
:Parameters: struct kvm_cpuid2 (in/out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_cpuid2 {
|
|
__u32 nent;
|
|
__u32 padding;
|
|
struct kvm_cpuid_entry2 entries[0];
|
|
};
|
|
|
|
struct kvm_cpuid_entry2 {
|
|
__u32 function;
|
|
__u32 index;
|
|
__u32 flags;
|
|
__u32 eax;
|
|
__u32 ebx;
|
|
__u32 ecx;
|
|
__u32 edx;
|
|
__u32 padding[3];
|
|
};
|
|
|
|
This ioctl returns x86 cpuid features leaves related to Hyper-V emulation in
|
|
KVM. Userspace can use the information returned by this ioctl to construct
|
|
cpuid information presented to guests consuming Hyper-V enlightenments (e.g.
|
|
Windows or Hyper-V guests).
|
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|
|
CPUID feature leaves returned by this ioctl are defined by Hyper-V Top Level
|
|
Functional Specification (TLFS). These leaves can't be obtained with
|
|
KVM_GET_SUPPORTED_CPUID ioctl because some of them intersect with KVM feature
|
|
leaves (0x40000000, 0x40000001).
|
|
|
|
Currently, the following list of CPUID leaves are returned:
|
|
|
|
- HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS
|
|
- HYPERV_CPUID_INTERFACE
|
|
- HYPERV_CPUID_VERSION
|
|
- HYPERV_CPUID_FEATURES
|
|
- HYPERV_CPUID_ENLIGHTMENT_INFO
|
|
- HYPERV_CPUID_IMPLEMENT_LIMITS
|
|
- HYPERV_CPUID_NESTED_FEATURES
|
|
- HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS
|
|
- HYPERV_CPUID_SYNDBG_INTERFACE
|
|
- HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES
|
|
|
|
Userspace invokes KVM_GET_SUPPORTED_HV_CPUID by passing a kvm_cpuid2 structure
|
|
with the 'nent' field indicating the number of entries in the variable-size
|
|
array 'entries'. If the number of entries is too low to describe all Hyper-V
|
|
feature leaves, an error (E2BIG) is returned. If the number is more or equal
|
|
to the number of Hyper-V feature leaves, the 'nent' field is adjusted to the
|
|
number of valid entries in the 'entries' array, which is then filled.
|
|
|
|
'index' and 'flags' fields in 'struct kvm_cpuid_entry2' are currently reserved,
|
|
userspace should not expect to get any particular value there.
|
|
|
|
Note, vcpu version of KVM_GET_SUPPORTED_HV_CPUID is currently deprecated. Unlike
|
|
system ioctl which exposes all supported feature bits unconditionally, vcpu
|
|
version has the following quirks:
|
|
|
|
- HYPERV_CPUID_NESTED_FEATURES leaf and HV_X64_ENLIGHTENED_VMCS_RECOMMENDED
|
|
feature bit are only exposed when Enlightened VMCS was previously enabled
|
|
on the corresponding vCPU (KVM_CAP_HYPERV_ENLIGHTENED_VMCS).
|
|
- HV_STIMER_DIRECT_MODE_AVAILABLE bit is only exposed with in-kernel LAPIC.
|
|
(presumes KVM_CREATE_IRQCHIP has already been called).
|
|
|
|
4.119 KVM_ARM_VCPU_FINALIZE
|
|
---------------------------
|
|
|
|
:Architectures: arm64
|
|
:Type: vcpu ioctl
|
|
:Parameters: int feature (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Errors:
|
|
|
|
====== ==============================================================
|
|
EPERM feature not enabled, needs configuration, or already finalized
|
|
EINVAL feature unknown or not present
|
|
====== ==============================================================
|
|
|
|
Recognised values for feature:
|
|
|
|
===== ===========================================
|
|
arm64 KVM_ARM_VCPU_SVE (requires KVM_CAP_ARM_SVE)
|
|
===== ===========================================
|
|
|
|
Finalizes the configuration of the specified vcpu feature.
|
|
|
|
The vcpu must already have been initialised, enabling the affected feature, by
|
|
means of a successful KVM_ARM_VCPU_INIT call with the appropriate flag set in
|
|
features[].
|
|
|
|
For affected vcpu features, this is a mandatory step that must be performed
|
|
before the vcpu is fully usable.
|
|
|
|
Between KVM_ARM_VCPU_INIT and KVM_ARM_VCPU_FINALIZE, the feature may be
|
|
configured by use of ioctls such as KVM_SET_ONE_REG. The exact configuration
|
|
that should be performaned and how to do it are feature-dependent.
|
|
|
|
Other calls that depend on a particular feature being finalized, such as
|
|
KVM_RUN, KVM_GET_REG_LIST, KVM_GET_ONE_REG and KVM_SET_ONE_REG, will fail with
|
|
-EPERM unless the feature has already been finalized by means of a
|
|
KVM_ARM_VCPU_FINALIZE call.
|
|
|
|
See KVM_ARM_VCPU_INIT for details of vcpu features that require finalization
|
|
using this ioctl.
|
|
|
|
4.120 KVM_SET_PMU_EVENT_FILTER
|
|
------------------------------
|
|
|
|
:Capability: KVM_CAP_PMU_EVENT_FILTER
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_pmu_event_filter (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_pmu_event_filter {
|
|
__u32 action;
|
|
__u32 nevents;
|
|
__u32 fixed_counter_bitmap;
|
|
__u32 flags;
|
|
__u32 pad[4];
|
|
__u64 events[0];
|
|
};
|
|
|
|
This ioctl restricts the set of PMU events that the guest can program.
|
|
The argument holds a list of events which will be allowed or denied.
|
|
The eventsel+umask of each event the guest attempts to program is compared
|
|
against the events field to determine whether the guest should have access.
|
|
The events field only controls general purpose counters; fixed purpose
|
|
counters are controlled by the fixed_counter_bitmap.
|
|
|
|
No flags are defined yet, the field must be zero.
|
|
|
|
Valid values for 'action'::
|
|
|
|
#define KVM_PMU_EVENT_ALLOW 0
|
|
#define KVM_PMU_EVENT_DENY 1
|
|
|
|
4.121 KVM_PPC_SVM_OFF
|
|
---------------------
|
|
|
|
:Capability: basic
|
|
:Architectures: powerpc
|
|
:Type: vm ioctl
|
|
:Parameters: none
|
|
:Returns: 0 on successful completion,
|
|
|
|
Errors:
|
|
|
|
====== ================================================================
|
|
EINVAL if ultravisor failed to terminate the secure guest
|
|
ENOMEM if hypervisor failed to allocate new radix page tables for guest
|
|
====== ================================================================
|
|
|
|
This ioctl is used to turn off the secure mode of the guest or transition
|
|
the guest from secure mode to normal mode. This is invoked when the guest
|
|
is reset. This has no effect if called for a normal guest.
|
|
|
|
This ioctl issues an ultravisor call to terminate the secure guest,
|
|
unpins the VPA pages and releases all the device pages that are used to
|
|
track the secure pages by hypervisor.
|
|
|
|
4.122 KVM_S390_NORMAL_RESET
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_S390_VCPU_RESETS
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0
|
|
|
|
This ioctl resets VCPU registers and control structures according to
|
|
the cpu reset definition in the POP (Principles Of Operation).
|
|
|
|
4.123 KVM_S390_INITIAL_RESET
|
|
----------------------------
|
|
|
|
:Capability: none
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0
|
|
|
|
This ioctl resets VCPU registers and control structures according to
|
|
the initial cpu reset definition in the POP. However, the cpu is not
|
|
put into ESA mode. This reset is a superset of the normal reset.
|
|
|
|
4.124 KVM_S390_CLEAR_RESET
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_S390_VCPU_RESETS
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0
|
|
|
|
This ioctl resets VCPU registers and control structures according to
|
|
the clear cpu reset definition in the POP. However, the cpu is not put
|
|
into ESA mode. This reset is a superset of the initial reset.
|
|
|
|
|
|
4.125 KVM_S390_PV_COMMAND
|
|
-------------------------
|
|
|
|
:Capability: KVM_CAP_S390_PROTECTED
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_pv_cmd
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
::
|
|
|
|
struct kvm_pv_cmd {
|
|
__u32 cmd; /* Command to be executed */
|
|
__u16 rc; /* Ultravisor return code */
|
|
__u16 rrc; /* Ultravisor return reason code */
|
|
__u64 data; /* Data or address */
|
|
__u32 flags; /* flags for future extensions. Must be 0 for now */
|
|
__u32 reserved[3];
|
|
};
|
|
|
|
**Ultravisor return codes**
|
|
The Ultravisor return (reason) codes are provided by the kernel if a
|
|
Ultravisor call has been executed to achieve the results expected by
|
|
the command. Therefore they are independent of the IOCTL return
|
|
code. If KVM changes `rc`, its value will always be greater than 0
|
|
hence setting it to 0 before issuing a PV command is advised to be
|
|
able to detect a change of `rc`.
|
|
|
|
**cmd values:**
|
|
|
|
KVM_PV_ENABLE
|
|
Allocate memory and register the VM with the Ultravisor, thereby
|
|
donating memory to the Ultravisor that will become inaccessible to
|
|
KVM. All existing CPUs are converted to protected ones. After this
|
|
command has succeeded, any CPU added via hotplug will become
|
|
protected during its creation as well.
|
|
|
|
Errors:
|
|
|
|
===== =============================
|
|
EINTR an unmasked signal is pending
|
|
===== =============================
|
|
|
|
KVM_PV_DISABLE
|
|
Deregister the VM from the Ultravisor and reclaim the memory that
|
|
had been donated to the Ultravisor, making it usable by the kernel
|
|
again. All registered VCPUs are converted back to non-protected
|
|
ones.
|
|
|
|
KVM_PV_VM_SET_SEC_PARMS
|
|
Pass the image header from VM memory to the Ultravisor in
|
|
preparation of image unpacking and verification.
|
|
|
|
KVM_PV_VM_UNPACK
|
|
Unpack (protect and decrypt) a page of the encrypted boot image.
|
|
|
|
KVM_PV_VM_VERIFY
|
|
Verify the integrity of the unpacked image. Only if this succeeds,
|
|
KVM is allowed to start protected VCPUs.
|
|
|
|
KVM_PV_INFO
|
|
:Capability: KVM_CAP_S390_PROTECTED_DUMP
|
|
|
|
Presents an API that provides Ultravisor related data to userspace
|
|
via subcommands. len_max is the size of the user space buffer,
|
|
len_written is KVM's indication of how much bytes of that buffer
|
|
were actually written to. len_written can be used to determine the
|
|
valid fields if more response fields are added in the future.
|
|
|
|
::
|
|
|
|
enum pv_cmd_info_id {
|
|
KVM_PV_INFO_VM,
|
|
KVM_PV_INFO_DUMP,
|
|
};
|
|
|
|
struct kvm_s390_pv_info_header {
|
|
__u32 id;
|
|
__u32 len_max;
|
|
__u32 len_written;
|
|
__u32 reserved;
|
|
};
|
|
|
|
struct kvm_s390_pv_info {
|
|
struct kvm_s390_pv_info_header header;
|
|
struct kvm_s390_pv_info_dump dump;
|
|
struct kvm_s390_pv_info_vm vm;
|
|
};
|
|
|
|
**subcommands:**
|
|
|
|
KVM_PV_INFO_VM
|
|
This subcommand provides basic Ultravisor information for PV
|
|
hosts. These values are likely also exported as files in the sysfs
|
|
firmware UV query interface but they are more easily available to
|
|
programs in this API.
|
|
|
|
The installed calls and feature_indication members provide the
|
|
installed UV calls and the UV's other feature indications.
|
|
|
|
The max_* members provide information about the maximum number of PV
|
|
vcpus, PV guests and PV guest memory size.
|
|
|
|
::
|
|
|
|
struct kvm_s390_pv_info_vm {
|
|
__u64 inst_calls_list[4];
|
|
__u64 max_cpus;
|
|
__u64 max_guests;
|
|
__u64 max_guest_addr;
|
|
__u64 feature_indication;
|
|
};
|
|
|
|
|
|
KVM_PV_INFO_DUMP
|
|
This subcommand provides information related to dumping PV guests.
|
|
|
|
::
|
|
|
|
struct kvm_s390_pv_info_dump {
|
|
__u64 dump_cpu_buffer_len;
|
|
__u64 dump_config_mem_buffer_per_1m;
|
|
__u64 dump_config_finalize_len;
|
|
};
|
|
|
|
KVM_PV_DUMP
|
|
:Capability: KVM_CAP_S390_PROTECTED_DUMP
|
|
|
|
Presents an API that provides calls which facilitate dumping a
|
|
protected VM.
|
|
|
|
::
|
|
|
|
struct kvm_s390_pv_dmp {
|
|
__u64 subcmd;
|
|
__u64 buff_addr;
|
|
__u64 buff_len;
|
|
__u64 gaddr; /* For dump storage state */
|
|
};
|
|
|
|
**subcommands:**
|
|
|
|
KVM_PV_DUMP_INIT
|
|
Initializes the dump process of a protected VM. If this call does
|
|
not succeed all other subcommands will fail with -EINVAL. This
|
|
subcommand will return -EINVAL if a dump process has not yet been
|
|
completed.
|
|
|
|
Not all PV vms can be dumped, the owner needs to set `dump
|
|
allowed` PCF bit 34 in the SE header to allow dumping.
|
|
|
|
KVM_PV_DUMP_CONFIG_STOR_STATE
|
|
Stores `buff_len` bytes of tweak component values starting with
|
|
the 1MB block specified by the absolute guest address
|
|
(`gaddr`). `buff_len` needs to be `conf_dump_storage_state_len`
|
|
aligned and at least >= the `conf_dump_storage_state_len` value
|
|
provided by the dump uv_info data. buff_user might be written to
|
|
even if an error rc is returned. For instance if we encounter a
|
|
fault after writing the first page of data.
|
|
|
|
KVM_PV_DUMP_COMPLETE
|
|
If the subcommand succeeds it completes the dump process and lets
|
|
KVM_PV_DUMP_INIT be called again.
|
|
|
|
On success `conf_dump_finalize_len` bytes of completion data will be
|
|
stored to the `buff_addr`. The completion data contains a key
|
|
derivation seed, IV, tweak nonce and encryption keys as well as an
|
|
authentication tag all of which are needed to decrypt the dump at a
|
|
later time.
|
|
|
|
|
|
4.126 KVM_X86_SET_MSR_FILTER
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_X86_MSR_FILTER
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_msr_filter
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
::
|
|
|
|
struct kvm_msr_filter_range {
|
|
#define KVM_MSR_FILTER_READ (1 << 0)
|
|
#define KVM_MSR_FILTER_WRITE (1 << 1)
|
|
__u32 flags;
|
|
__u32 nmsrs; /* number of msrs in bitmap */
|
|
__u32 base; /* MSR index the bitmap starts at */
|
|
__u8 *bitmap; /* a 1 bit allows the operations in flags, 0 denies */
|
|
};
|
|
|
|
#define KVM_MSR_FILTER_MAX_RANGES 16
|
|
struct kvm_msr_filter {
|
|
#define KVM_MSR_FILTER_DEFAULT_ALLOW (0 << 0)
|
|
#define KVM_MSR_FILTER_DEFAULT_DENY (1 << 0)
|
|
__u32 flags;
|
|
struct kvm_msr_filter_range ranges[KVM_MSR_FILTER_MAX_RANGES];
|
|
};
|
|
|
|
flags values for ``struct kvm_msr_filter_range``:
|
|
|
|
``KVM_MSR_FILTER_READ``
|
|
|
|
Filter read accesses to MSRs using the given bitmap. A 0 in the bitmap
|
|
indicates that a read should immediately fail, while a 1 indicates that
|
|
a read for a particular MSR should be handled regardless of the default
|
|
filter action.
|
|
|
|
``KVM_MSR_FILTER_WRITE``
|
|
|
|
Filter write accesses to MSRs using the given bitmap. A 0 in the bitmap
|
|
indicates that a write should immediately fail, while a 1 indicates that
|
|
a write for a particular MSR should be handled regardless of the default
|
|
filter action.
|
|
|
|
``KVM_MSR_FILTER_READ | KVM_MSR_FILTER_WRITE``
|
|
|
|
Filter both read and write accesses to MSRs using the given bitmap. A 0
|
|
in the bitmap indicates that both reads and writes should immediately fail,
|
|
while a 1 indicates that reads and writes for a particular MSR are not
|
|
filtered by this range.
|
|
|
|
flags values for ``struct kvm_msr_filter``:
|
|
|
|
``KVM_MSR_FILTER_DEFAULT_ALLOW``
|
|
|
|
If no filter range matches an MSR index that is getting accessed, KVM will
|
|
fall back to allowing access to the MSR.
|
|
|
|
``KVM_MSR_FILTER_DEFAULT_DENY``
|
|
|
|
If no filter range matches an MSR index that is getting accessed, KVM will
|
|
fall back to rejecting access to the MSR. In this mode, all MSRs that should
|
|
be processed by KVM need to explicitly be marked as allowed in the bitmaps.
|
|
|
|
This ioctl allows user space to define up to 16 bitmaps of MSR ranges to
|
|
specify whether a certain MSR access should be explicitly filtered for or not.
|
|
|
|
If this ioctl has never been invoked, MSR accesses are not guarded and the
|
|
default KVM in-kernel emulation behavior is fully preserved.
|
|
|
|
Calling this ioctl with an empty set of ranges (all nmsrs == 0) disables MSR
|
|
filtering. In that mode, ``KVM_MSR_FILTER_DEFAULT_DENY`` is invalid and causes
|
|
an error.
|
|
|
|
As soon as the filtering is in place, every MSR access is processed through
|
|
the filtering except for accesses to the x2APIC MSRs (from 0x800 to 0x8ff);
|
|
x2APIC MSRs are always allowed, independent of the ``default_allow`` setting,
|
|
and their behavior depends on the ``X2APIC_ENABLE`` bit of the APIC base
|
|
register.
|
|
|
|
If a bit is within one of the defined ranges, read and write accesses are
|
|
guarded by the bitmap's value for the MSR index if the kind of access
|
|
is included in the ``struct kvm_msr_filter_range`` flags. If no range
|
|
cover this particular access, the behavior is determined by the flags
|
|
field in the kvm_msr_filter struct: ``KVM_MSR_FILTER_DEFAULT_ALLOW``
|
|
and ``KVM_MSR_FILTER_DEFAULT_DENY``.
|
|
|
|
Each bitmap range specifies a range of MSRs to potentially allow access on.
|
|
The range goes from MSR index [base .. base+nmsrs]. The flags field
|
|
indicates whether reads, writes or both reads and writes are filtered
|
|
by setting a 1 bit in the bitmap for the corresponding MSR index.
|
|
|
|
If an MSR access is not permitted through the filtering, it generates a
|
|
#GP inside the guest. When combined with KVM_CAP_X86_USER_SPACE_MSR, that
|
|
allows user space to deflect and potentially handle various MSR accesses
|
|
into user space.
|
|
|
|
Note, invoking this ioctl with a vCPU is running is inherently racy. However,
|
|
KVM does guarantee that vCPUs will see either the previous filter or the new
|
|
filter, e.g. MSRs with identical settings in both the old and new filter will
|
|
have deterministic behavior.
|
|
|
|
4.127 KVM_XEN_HVM_SET_ATTR
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_xen_hvm_attr
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
::
|
|
|
|
struct kvm_xen_hvm_attr {
|
|
__u16 type;
|
|
__u16 pad[3];
|
|
union {
|
|
__u8 long_mode;
|
|
__u8 vector;
|
|
struct {
|
|
__u64 gfn;
|
|
} shared_info;
|
|
struct {
|
|
__u32 send_port;
|
|
__u32 type; /* EVTCHNSTAT_ipi / EVTCHNSTAT_interdomain */
|
|
__u32 flags;
|
|
union {
|
|
struct {
|
|
__u32 port;
|
|
__u32 vcpu;
|
|
__u32 priority;
|
|
} port;
|
|
struct {
|
|
__u32 port; /* Zero for eventfd */
|
|
__s32 fd;
|
|
} eventfd;
|
|
__u32 padding[4];
|
|
} deliver;
|
|
} evtchn;
|
|
__u32 xen_version;
|
|
__u64 pad[8];
|
|
} u;
|
|
};
|
|
|
|
type values:
|
|
|
|
KVM_XEN_ATTR_TYPE_LONG_MODE
|
|
Sets the ABI mode of the VM to 32-bit or 64-bit (long mode). This
|
|
determines the layout of the shared info pages exposed to the VM.
|
|
|
|
KVM_XEN_ATTR_TYPE_SHARED_INFO
|
|
Sets the guest physical frame number at which the Xen "shared info"
|
|
page resides. Note that although Xen places vcpu_info for the first
|
|
32 vCPUs in the shared_info page, KVM does not automatically do so
|
|
and instead requires that KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO be used
|
|
explicitly even when the vcpu_info for a given vCPU resides at the
|
|
"default" location in the shared_info page. This is because KVM is
|
|
not aware of the Xen CPU id which is used as the index into the
|
|
vcpu_info[] array, so cannot know the correct default location.
|
|
|
|
Note that the shared info page may be constantly written to by KVM;
|
|
it contains the event channel bitmap used to deliver interrupts to
|
|
a Xen guest, amongst other things. It is exempt from dirty tracking
|
|
mechanisms — KVM will not explicitly mark the page as dirty each
|
|
time an event channel interrupt is delivered to the guest! Thus,
|
|
userspace should always assume that the designated GFN is dirty if
|
|
any vCPU has been running or any event channel interrupts can be
|
|
routed to the guest.
|
|
|
|
KVM_XEN_ATTR_TYPE_UPCALL_VECTOR
|
|
Sets the exception vector used to deliver Xen event channel upcalls.
|
|
This is the HVM-wide vector injected directly by the hypervisor
|
|
(not through the local APIC), typically configured by a guest via
|
|
HVM_PARAM_CALLBACK_IRQ.
|
|
|
|
KVM_XEN_ATTR_TYPE_EVTCHN
|
|
This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
|
|
support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It configures
|
|
an outbound port number for interception of EVTCHNOP_send requests
|
|
from the guest. A given sending port number may be directed back
|
|
to a specified vCPU (by APIC ID) / port / priority on the guest,
|
|
or to trigger events on an eventfd. The vCPU and priority can be
|
|
changed by setting KVM_XEN_EVTCHN_UPDATE in a subsequent call,
|
|
but other fields cannot change for a given sending port. A port
|
|
mapping is removed by using KVM_XEN_EVTCHN_DEASSIGN in the flags
|
|
field.
|
|
|
|
KVM_XEN_ATTR_TYPE_XEN_VERSION
|
|
This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
|
|
support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It configures
|
|
the 32-bit version code returned to the guest when it invokes the
|
|
XENVER_version call; typically (XEN_MAJOR << 16 | XEN_MINOR). PV
|
|
Xen guests will often use this to as a dummy hypercall to trigger
|
|
event channel delivery, so responding within the kernel without
|
|
exiting to userspace is beneficial.
|
|
|
|
4.127 KVM_XEN_HVM_GET_ATTR
|
|
--------------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_xen_hvm_attr
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
Allows Xen VM attributes to be read. For the structure and types,
|
|
see KVM_XEN_HVM_SET_ATTR above. The KVM_XEN_ATTR_TYPE_EVTCHN
|
|
attribute cannot be read.
|
|
|
|
4.128 KVM_XEN_VCPU_SET_ATTR
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xen_vcpu_attr
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
::
|
|
|
|
struct kvm_xen_vcpu_attr {
|
|
__u16 type;
|
|
__u16 pad[3];
|
|
union {
|
|
__u64 gpa;
|
|
__u64 pad[4];
|
|
struct {
|
|
__u64 state;
|
|
__u64 state_entry_time;
|
|
__u64 time_running;
|
|
__u64 time_runnable;
|
|
__u64 time_blocked;
|
|
__u64 time_offline;
|
|
} runstate;
|
|
__u32 vcpu_id;
|
|
struct {
|
|
__u32 port;
|
|
__u32 priority;
|
|
__u64 expires_ns;
|
|
} timer;
|
|
__u8 vector;
|
|
} u;
|
|
};
|
|
|
|
type values:
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO
|
|
Sets the guest physical address of the vcpu_info for a given vCPU.
|
|
As with the shared_info page for the VM, the corresponding page may be
|
|
dirtied at any time if event channel interrupt delivery is enabled, so
|
|
userspace should always assume that the page is dirty without relying
|
|
on dirty logging.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO
|
|
Sets the guest physical address of an additional pvclock structure
|
|
for a given vCPU. This is typically used for guest vsyscall support.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR
|
|
Sets the guest physical address of the vcpu_runstate_info for a given
|
|
vCPU. This is how a Xen guest tracks CPU state such as steal time.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT
|
|
Sets the runstate (RUNSTATE_running/_runnable/_blocked/_offline) of
|
|
the given vCPU from the .u.runstate.state member of the structure.
|
|
KVM automatically accounts running and runnable time but blocked
|
|
and offline states are only entered explicitly.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA
|
|
Sets all fields of the vCPU runstate data from the .u.runstate member
|
|
of the structure, including the current runstate. The state_entry_time
|
|
must equal the sum of the other four times.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST
|
|
This *adds* the contents of the .u.runstate members of the structure
|
|
to the corresponding members of the given vCPU's runstate data, thus
|
|
permitting atomic adjustments to the runstate times. The adjustment
|
|
to the state_entry_time must equal the sum of the adjustments to the
|
|
other four times. The state field must be set to -1, or to a valid
|
|
runstate value (RUNSTATE_running, RUNSTATE_runnable, RUNSTATE_blocked
|
|
or RUNSTATE_offline) to set the current accounted state as of the
|
|
adjusted state_entry_time.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID
|
|
This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
|
|
support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the Xen
|
|
vCPU ID of the given vCPU, to allow timer-related VCPU operations to
|
|
be intercepted by KVM.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_TIMER
|
|
This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
|
|
support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the
|
|
event channel port/priority for the VIRQ_TIMER of the vCPU, as well
|
|
as allowing a pending timer to be saved/restored.
|
|
|
|
KVM_XEN_VCPU_ATTR_TYPE_UPCALL_VECTOR
|
|
This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
|
|
support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the
|
|
per-vCPU local APIC upcall vector, configured by a Xen guest with
|
|
the HVMOP_set_evtchn_upcall_vector hypercall. This is typically
|
|
used by Windows guests, and is distinct from the HVM-wide upcall
|
|
vector configured with HVM_PARAM_CALLBACK_IRQ.
|
|
|
|
|
|
4.129 KVM_XEN_VCPU_GET_ATTR
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xen_vcpu_attr
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
Allows Xen vCPU attributes to be read. For the structure and types,
|
|
see KVM_XEN_VCPU_SET_ATTR above.
|
|
|
|
The KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST type may not be used
|
|
with the KVM_XEN_VCPU_GET_ATTR ioctl.
|
|
|
|
4.130 KVM_ARM_MTE_COPY_TAGS
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_ARM_MTE
|
|
:Architectures: arm64
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_arm_copy_mte_tags
|
|
:Returns: number of bytes copied, < 0 on error (-EINVAL for incorrect
|
|
arguments, -EFAULT if memory cannot be accessed).
|
|
|
|
::
|
|
|
|
struct kvm_arm_copy_mte_tags {
|
|
__u64 guest_ipa;
|
|
__u64 length;
|
|
void __user *addr;
|
|
__u64 flags;
|
|
__u64 reserved[2];
|
|
};
|
|
|
|
Copies Memory Tagging Extension (MTE) tags to/from guest tag memory. The
|
|
``guest_ipa`` and ``length`` fields must be ``PAGE_SIZE`` aligned. The ``addr``
|
|
field must point to a buffer which the tags will be copied to or from.
|
|
|
|
``flags`` specifies the direction of copy, either ``KVM_ARM_TAGS_TO_GUEST`` or
|
|
``KVM_ARM_TAGS_FROM_GUEST``.
|
|
|
|
The size of the buffer to store the tags is ``(length / 16)`` bytes
|
|
(granules in MTE are 16 bytes long). Each byte contains a single tag
|
|
value. This matches the format of ``PTRACE_PEEKMTETAGS`` and
|
|
``PTRACE_POKEMTETAGS``.
|
|
|
|
If an error occurs before any data is copied then a negative error code is
|
|
returned. If some tags have been copied before an error occurs then the number
|
|
of bytes successfully copied is returned. If the call completes successfully
|
|
then ``length`` is returned.
|
|
|
|
4.131 KVM_GET_SREGS2
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_SREGS2
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_sregs2 (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Reads special registers from the vcpu.
|
|
This ioctl (when supported) replaces the KVM_GET_SREGS.
|
|
|
|
::
|
|
|
|
struct kvm_sregs2 {
|
|
/* out (KVM_GET_SREGS2) / in (KVM_SET_SREGS2) */
|
|
struct kvm_segment cs, ds, es, fs, gs, ss;
|
|
struct kvm_segment tr, ldt;
|
|
struct kvm_dtable gdt, idt;
|
|
__u64 cr0, cr2, cr3, cr4, cr8;
|
|
__u64 efer;
|
|
__u64 apic_base;
|
|
__u64 flags;
|
|
__u64 pdptrs[4];
|
|
};
|
|
|
|
flags values for ``kvm_sregs2``:
|
|
|
|
``KVM_SREGS2_FLAGS_PDPTRS_VALID``
|
|
|
|
Indicates thats the struct contain valid PDPTR values.
|
|
|
|
|
|
4.132 KVM_SET_SREGS2
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_SREGS2
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_sregs2 (in)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Writes special registers into the vcpu.
|
|
See KVM_GET_SREGS2 for the data structures.
|
|
This ioctl (when supported) replaces the KVM_SET_SREGS.
|
|
|
|
4.133 KVM_GET_STATS_FD
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_STATS_BINARY_FD
|
|
:Architectures: all
|
|
:Type: vm ioctl, vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: statistics file descriptor on success, < 0 on error
|
|
|
|
Errors:
|
|
|
|
====== ======================================================
|
|
ENOMEM if the fd could not be created due to lack of memory
|
|
EMFILE if the number of opened files exceeds the limit
|
|
====== ======================================================
|
|
|
|
The returned file descriptor can be used to read VM/vCPU statistics data in
|
|
binary format. The data in the file descriptor consists of four blocks
|
|
organized as follows:
|
|
|
|
+-------------+
|
|
| Header |
|
|
+-------------+
|
|
| id string |
|
|
+-------------+
|
|
| Descriptors |
|
|
+-------------+
|
|
| Stats Data |
|
|
+-------------+
|
|
|
|
Apart from the header starting at offset 0, please be aware that it is
|
|
not guaranteed that the four blocks are adjacent or in the above order;
|
|
the offsets of the id, descriptors and data blocks are found in the
|
|
header. However, all four blocks are aligned to 64 bit offsets in the
|
|
file and they do not overlap.
|
|
|
|
All blocks except the data block are immutable. Userspace can read them
|
|
only one time after retrieving the file descriptor, and then use ``pread`` or
|
|
``lseek`` to read the statistics repeatedly.
|
|
|
|
All data is in system endianness.
|
|
|
|
The format of the header is as follows::
|
|
|
|
struct kvm_stats_header {
|
|
__u32 flags;
|
|
__u32 name_size;
|
|
__u32 num_desc;
|
|
__u32 id_offset;
|
|
__u32 desc_offset;
|
|
__u32 data_offset;
|
|
};
|
|
|
|
The ``flags`` field is not used at the moment. It is always read as 0.
|
|
|
|
The ``name_size`` field is the size (in byte) of the statistics name string
|
|
(including trailing '\0') which is contained in the "id string" block and
|
|
appended at the end of every descriptor.
|
|
|
|
The ``num_desc`` field is the number of descriptors that are included in the
|
|
descriptor block. (The actual number of values in the data block may be
|
|
larger, since each descriptor may comprise more than one value).
|
|
|
|
The ``id_offset`` field is the offset of the id string from the start of the
|
|
file indicated by the file descriptor. It is a multiple of 8.
|
|
|
|
The ``desc_offset`` field is the offset of the Descriptors block from the start
|
|
of the file indicated by the file descriptor. It is a multiple of 8.
|
|
|
|
The ``data_offset`` field is the offset of the Stats Data block from the start
|
|
of the file indicated by the file descriptor. It is a multiple of 8.
|
|
|
|
The id string block contains a string which identifies the file descriptor on
|
|
which KVM_GET_STATS_FD was invoked. The size of the block, including the
|
|
trailing ``'\0'``, is indicated by the ``name_size`` field in the header.
|
|
|
|
The descriptors block is only needed to be read once for the lifetime of the
|
|
file descriptor contains a sequence of ``struct kvm_stats_desc``, each followed
|
|
by a string of size ``name_size``.
|
|
::
|
|
|
|
#define KVM_STATS_TYPE_SHIFT 0
|
|
#define KVM_STATS_TYPE_MASK (0xF << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_CUMULATIVE (0x0 << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_INSTANT (0x1 << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_PEAK (0x2 << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_LINEAR_HIST (0x3 << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_LOG_HIST (0x4 << KVM_STATS_TYPE_SHIFT)
|
|
#define KVM_STATS_TYPE_MAX KVM_STATS_TYPE_LOG_HIST
|
|
|
|
#define KVM_STATS_UNIT_SHIFT 4
|
|
#define KVM_STATS_UNIT_MASK (0xF << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_NONE (0x0 << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_BYTES (0x1 << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_SECONDS (0x2 << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_CYCLES (0x3 << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_BOOLEAN (0x4 << KVM_STATS_UNIT_SHIFT)
|
|
#define KVM_STATS_UNIT_MAX KVM_STATS_UNIT_BOOLEAN
|
|
|
|
#define KVM_STATS_BASE_SHIFT 8
|
|
#define KVM_STATS_BASE_MASK (0xF << KVM_STATS_BASE_SHIFT)
|
|
#define KVM_STATS_BASE_POW10 (0x0 << KVM_STATS_BASE_SHIFT)
|
|
#define KVM_STATS_BASE_POW2 (0x1 << KVM_STATS_BASE_SHIFT)
|
|
#define KVM_STATS_BASE_MAX KVM_STATS_BASE_POW2
|
|
|
|
struct kvm_stats_desc {
|
|
__u32 flags;
|
|
__s16 exponent;
|
|
__u16 size;
|
|
__u32 offset;
|
|
__u32 bucket_size;
|
|
char name[];
|
|
};
|
|
|
|
The ``flags`` field contains the type and unit of the statistics data described
|
|
by this descriptor. Its endianness is CPU native.
|
|
The following flags are supported:
|
|
|
|
Bits 0-3 of ``flags`` encode the type:
|
|
|
|
* ``KVM_STATS_TYPE_CUMULATIVE``
|
|
The statistics reports a cumulative count. The value of data can only be increased.
|
|
Most of the counters used in KVM are of this type.
|
|
The corresponding ``size`` field for this type is always 1.
|
|
All cumulative statistics data are read/write.
|
|
* ``KVM_STATS_TYPE_INSTANT``
|
|
The statistics reports an instantaneous value. Its value can be increased or
|
|
decreased. This type is usually used as a measurement of some resources,
|
|
like the number of dirty pages, the number of large pages, etc.
|
|
All instant statistics are read only.
|
|
The corresponding ``size`` field for this type is always 1.
|
|
* ``KVM_STATS_TYPE_PEAK``
|
|
The statistics data reports a peak value, for example the maximum number
|
|
of items in a hash table bucket, the longest time waited and so on.
|
|
The value of data can only be increased.
|
|
The corresponding ``size`` field for this type is always 1.
|
|
* ``KVM_STATS_TYPE_LINEAR_HIST``
|
|
The statistic is reported as a linear histogram. The number of
|
|
buckets is specified by the ``size`` field. The size of buckets is specified
|
|
by the ``hist_param`` field. The range of the Nth bucket (1 <= N < ``size``)
|
|
is [``hist_param``*(N-1), ``hist_param``*N), while the range of the last
|
|
bucket is [``hist_param``*(``size``-1), +INF). (+INF means positive infinity
|
|
value.)
|
|
* ``KVM_STATS_TYPE_LOG_HIST``
|
|
The statistic is reported as a logarithmic histogram. The number of
|
|
buckets is specified by the ``size`` field. The range of the first bucket is
|
|
[0, 1), while the range of the last bucket is [pow(2, ``size``-2), +INF).
|
|
Otherwise, The Nth bucket (1 < N < ``size``) covers
|
|
[pow(2, N-2), pow(2, N-1)).
|
|
|
|
Bits 4-7 of ``flags`` encode the unit:
|
|
|
|
* ``KVM_STATS_UNIT_NONE``
|
|
There is no unit for the value of statistics data. This usually means that
|
|
the value is a simple counter of an event.
|
|
* ``KVM_STATS_UNIT_BYTES``
|
|
It indicates that the statistics data is used to measure memory size, in the
|
|
unit of Byte, KiByte, MiByte, GiByte, etc. The unit of the data is
|
|
determined by the ``exponent`` field in the descriptor.
|
|
* ``KVM_STATS_UNIT_SECONDS``
|
|
It indicates that the statistics data is used to measure time or latency.
|
|
* ``KVM_STATS_UNIT_CYCLES``
|
|
It indicates that the statistics data is used to measure CPU clock cycles.
|
|
* ``KVM_STATS_UNIT_BOOLEAN``
|
|
It indicates that the statistic will always be either 0 or 1. Boolean
|
|
statistics of "peak" type will never go back from 1 to 0. Boolean
|
|
statistics can be linear histograms (with two buckets) but not logarithmic
|
|
histograms.
|
|
|
|
Note that, in the case of histograms, the unit applies to the bucket
|
|
ranges, while the bucket value indicates how many samples fell in the
|
|
bucket's range.
|
|
|
|
Bits 8-11 of ``flags``, together with ``exponent``, encode the scale of the
|
|
unit:
|
|
|
|
* ``KVM_STATS_BASE_POW10``
|
|
The scale is based on power of 10. It is used for measurement of time and
|
|
CPU clock cycles. For example, an exponent of -9 can be used with
|
|
``KVM_STATS_UNIT_SECONDS`` to express that the unit is nanoseconds.
|
|
* ``KVM_STATS_BASE_POW2``
|
|
The scale is based on power of 2. It is used for measurement of memory size.
|
|
For example, an exponent of 20 can be used with ``KVM_STATS_UNIT_BYTES`` to
|
|
express that the unit is MiB.
|
|
|
|
The ``size`` field is the number of values of this statistics data. Its
|
|
value is usually 1 for most of simple statistics. 1 means it contains an
|
|
unsigned 64bit data.
|
|
|
|
The ``offset`` field is the offset from the start of Data Block to the start of
|
|
the corresponding statistics data.
|
|
|
|
The ``bucket_size`` field is used as a parameter for histogram statistics data.
|
|
It is only used by linear histogram statistics data, specifying the size of a
|
|
bucket in the unit expressed by bits 4-11 of ``flags`` together with ``exponent``.
|
|
|
|
The ``name`` field is the name string of the statistics data. The name string
|
|
starts at the end of ``struct kvm_stats_desc``. The maximum length including
|
|
the trailing ``'\0'``, is indicated by ``name_size`` in the header.
|
|
|
|
The Stats Data block contains an array of 64-bit values in the same order
|
|
as the descriptors in Descriptors block.
|
|
|
|
4.134 KVM_GET_XSAVE2
|
|
--------------------
|
|
|
|
:Capability: KVM_CAP_XSAVE2
|
|
:Architectures: x86
|
|
:Type: vcpu ioctl
|
|
:Parameters: struct kvm_xsave (out)
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
|
|
::
|
|
|
|
struct kvm_xsave {
|
|
__u32 region[1024];
|
|
__u32 extra[0];
|
|
};
|
|
|
|
This ioctl would copy current vcpu's xsave struct to the userspace. It
|
|
copies as many bytes as are returned by KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2)
|
|
when invoked on the vm file descriptor. The size value returned by
|
|
KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will always be at least 4096.
|
|
Currently, it is only greater than 4096 if a dynamic feature has been
|
|
enabled with ``arch_prctl()``, but this may change in the future.
|
|
|
|
The offsets of the state save areas in struct kvm_xsave follow the contents
|
|
of CPUID leaf 0xD on the host.
|
|
|
|
4.135 KVM_XEN_HVM_EVTCHN_SEND
|
|
-----------------------------
|
|
|
|
:Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_EVTCHN_SEND
|
|
:Architectures: x86
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_irq_routing_xen_evtchn
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
|
|
::
|
|
|
|
struct kvm_irq_routing_xen_evtchn {
|
|
__u32 port;
|
|
__u32 vcpu;
|
|
__u32 priority;
|
|
};
|
|
|
|
This ioctl injects an event channel interrupt directly to the guest vCPU.
|
|
|
|
4.136 KVM_S390_PV_CPU_COMMAND
|
|
-----------------------------
|
|
|
|
:Capability: KVM_CAP_S390_PROTECTED_DUMP
|
|
:Architectures: s390
|
|
:Type: vcpu ioctl
|
|
:Parameters: none
|
|
:Returns: 0 on success, < 0 on error
|
|
|
|
This ioctl closely mirrors `KVM_S390_PV_COMMAND` but handles requests
|
|
for vcpus. It re-uses the kvm_s390_pv_dmp struct and hence also shares
|
|
the command ids.
|
|
|
|
**command:**
|
|
|
|
KVM_PV_DUMP
|
|
Presents an API that provides calls which facilitate dumping a vcpu
|
|
of a protected VM.
|
|
|
|
**subcommand:**
|
|
|
|
KVM_PV_DUMP_CPU
|
|
Provides encrypted dump data like register values.
|
|
The length of the returned data is provided by uv_info.guest_cpu_stor_len.
|
|
|
|
4.137 KVM_S390_ZPCI_OP
|
|
----------------------
|
|
|
|
:Capability: KVM_CAP_S390_ZPCI_OP
|
|
:Architectures: s390
|
|
:Type: vm ioctl
|
|
:Parameters: struct kvm_s390_zpci_op (in)
|
|
:Returns: 0 on success, <0 on error
|
|
|
|
Used to manage hardware-assisted virtualization features for zPCI devices.
|
|
|
|
Parameters are specified via the following structure::
|
|
|
|
struct kvm_s390_zpci_op {
|
|
/* in */
|
|
__u32 fh; /* target device */
|
|
__u8 op; /* operation to perform */
|
|
__u8 pad[3];
|
|
union {
|
|
/* for KVM_S390_ZPCIOP_REG_AEN */
|
|
struct {
|
|
__u64 ibv; /* Guest addr of interrupt bit vector */
|
|
__u64 sb; /* Guest addr of summary bit */
|
|
__u32 flags;
|
|
__u32 noi; /* Number of interrupts */
|
|
__u8 isc; /* Guest interrupt subclass */
|
|
__u8 sbo; /* Offset of guest summary bit vector */
|
|
__u16 pad;
|
|
} reg_aen;
|
|
__u64 reserved[8];
|
|
} u;
|
|
};
|
|
|
|
The type of operation is specified in the "op" field.
|
|
KVM_S390_ZPCIOP_REG_AEN is used to register the VM for adapter event
|
|
notification interpretation, which will allow firmware delivery of adapter
|
|
events directly to the vm, with KVM providing a backup delivery mechanism;
|
|
KVM_S390_ZPCIOP_DEREG_AEN is used to subsequently disable interpretation of
|
|
adapter event notifications.
|
|
|
|
The target zPCI function must also be specified via the "fh" field. For the
|
|
KVM_S390_ZPCIOP_REG_AEN operation, additional information to establish firmware
|
|
delivery must be provided via the "reg_aen" struct.
|
|
|
|
The "pad" and "reserved" fields may be used for future extensions and should be
|
|
set to 0s by userspace.
|
|
|
|
5. The kvm_run structure
|
|
========================
|
|
|
|
Application code obtains a pointer to the kvm_run structure by
|
|
mmap()ing a vcpu fd. From that point, application code can control
|
|
execution by changing fields in kvm_run prior to calling the KVM_RUN
|
|
ioctl, and obtain information about the reason KVM_RUN returned by
|
|
looking up structure members.
|
|
|
|
::
|
|
|
|
struct kvm_run {
|
|
/* in */
|
|
__u8 request_interrupt_window;
|
|
|
|
Request that KVM_RUN return when it becomes possible to inject external
|
|
interrupts into the guest. Useful in conjunction with KVM_INTERRUPT.
|
|
|
|
::
|
|
|
|
__u8 immediate_exit;
|
|
|
|
This field is polled once when KVM_RUN starts; if non-zero, KVM_RUN
|
|
exits immediately, returning -EINTR. In the common scenario where a
|
|
signal is used to "kick" a VCPU out of KVM_RUN, this field can be used
|
|
to avoid usage of KVM_SET_SIGNAL_MASK, which has worse scalability.
|
|
Rather than blocking the signal outside KVM_RUN, userspace can set up
|
|
a signal handler that sets run->immediate_exit to a non-zero value.
|
|
|
|
This field is ignored if KVM_CAP_IMMEDIATE_EXIT is not available.
|
|
|
|
::
|
|
|
|
__u8 padding1[6];
|
|
|
|
/* out */
|
|
__u32 exit_reason;
|
|
|
|
When KVM_RUN has returned successfully (return value 0), this informs
|
|
application code why KVM_RUN has returned. Allowable values for this
|
|
field are detailed below.
|
|
|
|
::
|
|
|
|
__u8 ready_for_interrupt_injection;
|
|
|
|
If request_interrupt_window has been specified, this field indicates
|
|
an interrupt can be injected now with KVM_INTERRUPT.
|
|
|
|
::
|
|
|
|
__u8 if_flag;
|
|
|
|
The value of the current interrupt flag. Only valid if in-kernel
|
|
local APIC is not used.
|
|
|
|
::
|
|
|
|
__u16 flags;
|
|
|
|
More architecture-specific flags detailing state of the VCPU that may
|
|
affect the device's behavior. Current defined flags::
|
|
|
|
/* x86, set if the VCPU is in system management mode */
|
|
#define KVM_RUN_X86_SMM (1 << 0)
|
|
/* x86, set if bus lock detected in VM */
|
|
#define KVM_RUN_BUS_LOCK (1 << 1)
|
|
/* arm64, set for KVM_EXIT_DEBUG */
|
|
#define KVM_DEBUG_ARCH_HSR_HIGH_VALID (1 << 0)
|
|
|
|
::
|
|
|
|
/* in (pre_kvm_run), out (post_kvm_run) */
|
|
__u64 cr8;
|
|
|
|
The value of the cr8 register. Only valid if in-kernel local APIC is
|
|
not used. Both input and output.
|
|
|
|
::
|
|
|
|
__u64 apic_base;
|
|
|
|
The value of the APIC BASE msr. Only valid if in-kernel local
|
|
APIC is not used. Both input and output.
|
|
|
|
::
|
|
|
|
union {
|
|
/* KVM_EXIT_UNKNOWN */
|
|
struct {
|
|
__u64 hardware_exit_reason;
|
|
} hw;
|
|
|
|
If exit_reason is KVM_EXIT_UNKNOWN, the vcpu has exited due to unknown
|
|
reasons. Further architecture-specific information is available in
|
|
hardware_exit_reason.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_FAIL_ENTRY */
|
|
struct {
|
|
__u64 hardware_entry_failure_reason;
|
|
__u32 cpu; /* if KVM_LAST_CPU */
|
|
} fail_entry;
|
|
|
|
If exit_reason is KVM_EXIT_FAIL_ENTRY, the vcpu could not be run due
|
|
to unknown reasons. Further architecture-specific information is
|
|
available in hardware_entry_failure_reason.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_EXCEPTION */
|
|
struct {
|
|
__u32 exception;
|
|
__u32 error_code;
|
|
} ex;
|
|
|
|
Unused.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_IO */
|
|
struct {
|
|
#define KVM_EXIT_IO_IN 0
|
|
#define KVM_EXIT_IO_OUT 1
|
|
__u8 direction;
|
|
__u8 size; /* bytes */
|
|
__u16 port;
|
|
__u32 count;
|
|
__u64 data_offset; /* relative to kvm_run start */
|
|
} io;
|
|
|
|
If exit_reason is KVM_EXIT_IO, then the vcpu has
|
|
executed a port I/O instruction which could not be satisfied by kvm.
|
|
data_offset describes where the data is located (KVM_EXIT_IO_OUT) or
|
|
where kvm expects application code to place the data for the next
|
|
KVM_RUN invocation (KVM_EXIT_IO_IN). Data format is a packed array.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_DEBUG */
|
|
struct {
|
|
struct kvm_debug_exit_arch arch;
|
|
} debug;
|
|
|
|
If the exit_reason is KVM_EXIT_DEBUG, then a vcpu is processing a debug event
|
|
for which architecture specific information is returned.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_MMIO */
|
|
struct {
|
|
__u64 phys_addr;
|
|
__u8 data[8];
|
|
__u32 len;
|
|
__u8 is_write;
|
|
} mmio;
|
|
|
|
If exit_reason is KVM_EXIT_MMIO, then the vcpu has
|
|
executed a memory-mapped I/O instruction which could not be satisfied
|
|
by kvm. The 'data' member contains the written data if 'is_write' is
|
|
true, and should be filled by application code otherwise.
|
|
|
|
The 'data' member contains, in its first 'len' bytes, the value as it would
|
|
appear if the VCPU performed a load or store of the appropriate width directly
|
|
to the byte array.
|
|
|
|
.. note::
|
|
|
|
For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_PAPR, KVM_EXIT_XEN,
|
|
KVM_EXIT_EPR, KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR the corresponding
|
|
operations are complete (and guest state is consistent) only after userspace
|
|
has re-entered the kernel with KVM_RUN. The kernel side will first finish
|
|
incomplete operations and then check for pending signals.
|
|
|
|
The pending state of the operation is not preserved in state which is
|
|
visible to userspace, thus userspace should ensure that the operation is
|
|
completed before performing a live migration. Userspace can re-enter the
|
|
guest with an unmasked signal pending or with the immediate_exit field set
|
|
to complete pending operations without allowing any further instructions
|
|
to be executed.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_HYPERCALL */
|
|
struct {
|
|
__u64 nr;
|
|
__u64 args[6];
|
|
__u64 ret;
|
|
__u32 longmode;
|
|
__u32 pad;
|
|
} hypercall;
|
|
|
|
Unused. This was once used for 'hypercall to userspace'. To implement
|
|
such functionality, use KVM_EXIT_IO (x86) or KVM_EXIT_MMIO (all except s390).
|
|
|
|
.. note:: KVM_EXIT_IO is significantly faster than KVM_EXIT_MMIO.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_TPR_ACCESS */
|
|
struct {
|
|
__u64 rip;
|
|
__u32 is_write;
|
|
__u32 pad;
|
|
} tpr_access;
|
|
|
|
To be documented (KVM_TPR_ACCESS_REPORTING).
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_S390_SIEIC */
|
|
struct {
|
|
__u8 icptcode;
|
|
__u64 mask; /* psw upper half */
|
|
__u64 addr; /* psw lower half */
|
|
__u16 ipa;
|
|
__u32 ipb;
|
|
} s390_sieic;
|
|
|
|
s390 specific.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_S390_RESET */
|
|
#define KVM_S390_RESET_POR 1
|
|
#define KVM_S390_RESET_CLEAR 2
|
|
#define KVM_S390_RESET_SUBSYSTEM 4
|
|
#define KVM_S390_RESET_CPU_INIT 8
|
|
#define KVM_S390_RESET_IPL 16
|
|
__u64 s390_reset_flags;
|
|
|
|
s390 specific.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_S390_UCONTROL */
|
|
struct {
|
|
__u64 trans_exc_code;
|
|
__u32 pgm_code;
|
|
} s390_ucontrol;
|
|
|
|
s390 specific. A page fault has occurred for a user controlled virtual
|
|
machine (KVM_VM_S390_UNCONTROL) on it's host page table that cannot be
|
|
resolved by the kernel.
|
|
The program code and the translation exception code that were placed
|
|
in the cpu's lowcore are presented here as defined by the z Architecture
|
|
Principles of Operation Book in the Chapter for Dynamic Address Translation
|
|
(DAT)
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_DCR */
|
|
struct {
|
|
__u32 dcrn;
|
|
__u32 data;
|
|
__u8 is_write;
|
|
} dcr;
|
|
|
|
Deprecated - was used for 440 KVM.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_OSI */
|
|
struct {
|
|
__u64 gprs[32];
|
|
} osi;
|
|
|
|
MOL uses a special hypercall interface it calls 'OSI'. To enable it, we catch
|
|
hypercalls and exit with this exit struct that contains all the guest gprs.
|
|
|
|
If exit_reason is KVM_EXIT_OSI, then the vcpu has triggered such a hypercall.
|
|
Userspace can now handle the hypercall and when it's done modify the gprs as
|
|
necessary. Upon guest entry all guest GPRs will then be replaced by the values
|
|
in this struct.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_PAPR_HCALL */
|
|
struct {
|
|
__u64 nr;
|
|
__u64 ret;
|
|
__u64 args[9];
|
|
} papr_hcall;
|
|
|
|
This is used on 64-bit PowerPC when emulating a pSeries partition,
|
|
e.g. with the 'pseries' machine type in qemu. It occurs when the
|
|
guest does a hypercall using the 'sc 1' instruction. The 'nr' field
|
|
contains the hypercall number (from the guest R3), and 'args' contains
|
|
the arguments (from the guest R4 - R12). Userspace should put the
|
|
return code in 'ret' and any extra returned values in args[].
|
|
The possible hypercalls are defined in the Power Architecture Platform
|
|
Requirements (PAPR) document available from www.power.org (free
|
|
developer registration required to access it).
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_S390_TSCH */
|
|
struct {
|
|
__u16 subchannel_id;
|
|
__u16 subchannel_nr;
|
|
__u32 io_int_parm;
|
|
__u32 io_int_word;
|
|
__u32 ipb;
|
|
__u8 dequeued;
|
|
} s390_tsch;
|
|
|
|
s390 specific. This exit occurs when KVM_CAP_S390_CSS_SUPPORT has been enabled
|
|
and TEST SUBCHANNEL was intercepted. If dequeued is set, a pending I/O
|
|
interrupt for the target subchannel has been dequeued and subchannel_id,
|
|
subchannel_nr, io_int_parm and io_int_word contain the parameters for that
|
|
interrupt. ipb is needed for instruction parameter decoding.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_EPR */
|
|
struct {
|
|
__u32 epr;
|
|
} epr;
|
|
|
|
On FSL BookE PowerPC chips, the interrupt controller has a fast patch
|
|
interrupt acknowledge path to the core. When the core successfully
|
|
delivers an interrupt, it automatically populates the EPR register with
|
|
the interrupt vector number and acknowledges the interrupt inside
|
|
the interrupt controller.
|
|
|
|
In case the interrupt controller lives in user space, we need to do
|
|
the interrupt acknowledge cycle through it to fetch the next to be
|
|
delivered interrupt vector using this exit.
|
|
|
|
It gets triggered whenever both KVM_CAP_PPC_EPR are enabled and an
|
|
external interrupt has just been delivered into the guest. User space
|
|
should put the acknowledged interrupt vector into the 'epr' field.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_SYSTEM_EVENT */
|
|
struct {
|
|
#define KVM_SYSTEM_EVENT_SHUTDOWN 1
|
|
#define KVM_SYSTEM_EVENT_RESET 2
|
|
#define KVM_SYSTEM_EVENT_CRASH 3
|
|
#define KVM_SYSTEM_EVENT_WAKEUP 4
|
|
#define KVM_SYSTEM_EVENT_SUSPEND 5
|
|
#define KVM_SYSTEM_EVENT_SEV_TERM 6
|
|
__u32 type;
|
|
__u32 ndata;
|
|
__u64 data[16];
|
|
} system_event;
|
|
|
|
If exit_reason is KVM_EXIT_SYSTEM_EVENT then the vcpu has triggered
|
|
a system-level event using some architecture specific mechanism (hypercall
|
|
or some special instruction). In case of ARM64, this is triggered using
|
|
HVC instruction based PSCI call from the vcpu.
|
|
|
|
The 'type' field describes the system-level event type.
|
|
Valid values for 'type' are:
|
|
|
|
- KVM_SYSTEM_EVENT_SHUTDOWN -- the guest has requested a shutdown of the
|
|
VM. Userspace is not obliged to honour this, and if it does honour
|
|
this does not need to destroy the VM synchronously (ie it may call
|
|
KVM_RUN again before shutdown finally occurs).
|
|
- KVM_SYSTEM_EVENT_RESET -- the guest has requested a reset of the VM.
|
|
As with SHUTDOWN, userspace can choose to ignore the request, or
|
|
to schedule the reset to occur in the future and may call KVM_RUN again.
|
|
- KVM_SYSTEM_EVENT_CRASH -- the guest crash occurred and the guest
|
|
has requested a crash condition maintenance. Userspace can choose
|
|
to ignore the request, or to gather VM memory core dump and/or
|
|
reset/shutdown of the VM.
|
|
- KVM_SYSTEM_EVENT_SEV_TERM -- an AMD SEV guest requested termination.
|
|
The guest physical address of the guest's GHCB is stored in `data[0]`.
|
|
- KVM_SYSTEM_EVENT_WAKEUP -- the exiting vCPU is in a suspended state and
|
|
KVM has recognized a wakeup event. Userspace may honor this event by
|
|
marking the exiting vCPU as runnable, or deny it and call KVM_RUN again.
|
|
- KVM_SYSTEM_EVENT_SUSPEND -- the guest has requested a suspension of
|
|
the VM.
|
|
|
|
If KVM_CAP_SYSTEM_EVENT_DATA is present, the 'data' field can contain
|
|
architecture specific information for the system-level event. Only
|
|
the first `ndata` items (possibly zero) of the data array are valid.
|
|
|
|
- for arm64, data[0] is set to KVM_SYSTEM_EVENT_RESET_FLAG_PSCI_RESET2 if
|
|
the guest issued a SYSTEM_RESET2 call according to v1.1 of the PSCI
|
|
specification.
|
|
|
|
- for RISC-V, data[0] is set to the value of the second argument of the
|
|
``sbi_system_reset`` call.
|
|
|
|
Previous versions of Linux defined a `flags` member in this struct. The
|
|
field is now aliased to `data[0]`. Userspace can assume that it is only
|
|
written if ndata is greater than 0.
|
|
|
|
For arm/arm64:
|
|
--------------
|
|
|
|
KVM_SYSTEM_EVENT_SUSPEND exits are enabled with the
|
|
KVM_CAP_ARM_SYSTEM_SUSPEND VM capability. If a guest invokes the PSCI
|
|
SYSTEM_SUSPEND function, KVM will exit to userspace with this event
|
|
type.
|
|
|
|
It is the sole responsibility of userspace to implement the PSCI
|
|
SYSTEM_SUSPEND call according to ARM DEN0022D.b 5.19 "SYSTEM_SUSPEND".
|
|
KVM does not change the vCPU's state before exiting to userspace, so
|
|
the call parameters are left in-place in the vCPU registers.
|
|
|
|
Userspace is _required_ to take action for such an exit. It must
|
|
either:
|
|
|
|
- Honor the guest request to suspend the VM. Userspace can request
|
|
in-kernel emulation of suspension by setting the calling vCPU's
|
|
state to KVM_MP_STATE_SUSPENDED. Userspace must configure the vCPU's
|
|
state according to the parameters passed to the PSCI function when
|
|
the calling vCPU is resumed. See ARM DEN0022D.b 5.19.1 "Intended use"
|
|
for details on the function parameters.
|
|
|
|
- Deny the guest request to suspend the VM. See ARM DEN0022D.b 5.19.2
|
|
"Caller responsibilities" for possible return values.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_IOAPIC_EOI */
|
|
struct {
|
|
__u8 vector;
|
|
} eoi;
|
|
|
|
Indicates that the VCPU's in-kernel local APIC received an EOI for a
|
|
level-triggered IOAPIC interrupt. This exit only triggers when the
|
|
IOAPIC is implemented in userspace (i.e. KVM_CAP_SPLIT_IRQCHIP is enabled);
|
|
the userspace IOAPIC should process the EOI and retrigger the interrupt if
|
|
it is still asserted. Vector is the LAPIC interrupt vector for which the
|
|
EOI was received.
|
|
|
|
::
|
|
|
|
struct kvm_hyperv_exit {
|
|
#define KVM_EXIT_HYPERV_SYNIC 1
|
|
#define KVM_EXIT_HYPERV_HCALL 2
|
|
#define KVM_EXIT_HYPERV_SYNDBG 3
|
|
__u32 type;
|
|
__u32 pad1;
|
|
union {
|
|
struct {
|
|
__u32 msr;
|
|
__u32 pad2;
|
|
__u64 control;
|
|
__u64 evt_page;
|
|
__u64 msg_page;
|
|
} synic;
|
|
struct {
|
|
__u64 input;
|
|
__u64 result;
|
|
__u64 params[2];
|
|
} hcall;
|
|
struct {
|
|
__u32 msr;
|
|
__u32 pad2;
|
|
__u64 control;
|
|
__u64 status;
|
|
__u64 send_page;
|
|
__u64 recv_page;
|
|
__u64 pending_page;
|
|
} syndbg;
|
|
} u;
|
|
};
|
|
/* KVM_EXIT_HYPERV */
|
|
struct kvm_hyperv_exit hyperv;
|
|
|
|
Indicates that the VCPU exits into userspace to process some tasks
|
|
related to Hyper-V emulation.
|
|
|
|
Valid values for 'type' are:
|
|
|
|
- KVM_EXIT_HYPERV_SYNIC -- synchronously notify user-space about
|
|
|
|
Hyper-V SynIC state change. Notification is used to remap SynIC
|
|
event/message pages and to enable/disable SynIC messages/events processing
|
|
in userspace.
|
|
|
|
- KVM_EXIT_HYPERV_SYNDBG -- synchronously notify user-space about
|
|
|
|
Hyper-V Synthetic debugger state change. Notification is used to either update
|
|
the pending_page location or to send a control command (send the buffer located
|
|
in send_page or recv a buffer to recv_page).
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_ARM_NISV */
|
|
struct {
|
|
__u64 esr_iss;
|
|
__u64 fault_ipa;
|
|
} arm_nisv;
|
|
|
|
Used on arm64 systems. If a guest accesses memory not in a memslot,
|
|
KVM will typically return to userspace and ask it to do MMIO emulation on its
|
|
behalf. However, for certain classes of instructions, no instruction decode
|
|
(direction, length of memory access) is provided, and fetching and decoding
|
|
the instruction from the VM is overly complicated to live in the kernel.
|
|
|
|
Historically, when this situation occurred, KVM would print a warning and kill
|
|
the VM. KVM assumed that if the guest accessed non-memslot memory, it was
|
|
trying to do I/O, which just couldn't be emulated, and the warning message was
|
|
phrased accordingly. However, what happened more often was that a guest bug
|
|
caused access outside the guest memory areas which should lead to a more
|
|
meaningful warning message and an external abort in the guest, if the access
|
|
did not fall within an I/O window.
|
|
|
|
Userspace implementations can query for KVM_CAP_ARM_NISV_TO_USER, and enable
|
|
this capability at VM creation. Once this is done, these types of errors will
|
|
instead return to userspace with KVM_EXIT_ARM_NISV, with the valid bits from
|
|
the ESR_EL2 in the esr_iss field, and the faulting IPA in the fault_ipa field.
|
|
Userspace can either fix up the access if it's actually an I/O access by
|
|
decoding the instruction from guest memory (if it's very brave) and continue
|
|
executing the guest, or it can decide to suspend, dump, or restart the guest.
|
|
|
|
Note that KVM does not skip the faulting instruction as it does for
|
|
KVM_EXIT_MMIO, but userspace has to emulate any change to the processing state
|
|
if it decides to decode and emulate the instruction.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_X86_RDMSR / KVM_EXIT_X86_WRMSR */
|
|
struct {
|
|
__u8 error; /* user -> kernel */
|
|
__u8 pad[7];
|
|
__u32 reason; /* kernel -> user */
|
|
__u32 index; /* kernel -> user */
|
|
__u64 data; /* kernel <-> user */
|
|
} msr;
|
|
|
|
Used on x86 systems. When the VM capability KVM_CAP_X86_USER_SPACE_MSR is
|
|
enabled, MSR accesses to registers that would invoke a #GP by KVM kernel code
|
|
will instead trigger a KVM_EXIT_X86_RDMSR exit for reads and KVM_EXIT_X86_WRMSR
|
|
exit for writes.
|
|
|
|
The "reason" field specifies why the MSR trap occurred. User space will only
|
|
receive MSR exit traps when a particular reason was requested during through
|
|
ENABLE_CAP. Currently valid exit reasons are:
|
|
|
|
KVM_MSR_EXIT_REASON_UNKNOWN - access to MSR that is unknown to KVM
|
|
KVM_MSR_EXIT_REASON_INVAL - access to invalid MSRs or reserved bits
|
|
KVM_MSR_EXIT_REASON_FILTER - access blocked by KVM_X86_SET_MSR_FILTER
|
|
|
|
For KVM_EXIT_X86_RDMSR, the "index" field tells user space which MSR the guest
|
|
wants to read. To respond to this request with a successful read, user space
|
|
writes the respective data into the "data" field and must continue guest
|
|
execution to ensure the read data is transferred into guest register state.
|
|
|
|
If the RDMSR request was unsuccessful, user space indicates that with a "1" in
|
|
the "error" field. This will inject a #GP into the guest when the VCPU is
|
|
executed again.
|
|
|
|
For KVM_EXIT_X86_WRMSR, the "index" field tells user space which MSR the guest
|
|
wants to write. Once finished processing the event, user space must continue
|
|
vCPU execution. If the MSR write was unsuccessful, user space also sets the
|
|
"error" field to "1".
|
|
|
|
::
|
|
|
|
|
|
struct kvm_xen_exit {
|
|
#define KVM_EXIT_XEN_HCALL 1
|
|
__u32 type;
|
|
union {
|
|
struct {
|
|
__u32 longmode;
|
|
__u32 cpl;
|
|
__u64 input;
|
|
__u64 result;
|
|
__u64 params[6];
|
|
} hcall;
|
|
} u;
|
|
};
|
|
/* KVM_EXIT_XEN */
|
|
struct kvm_hyperv_exit xen;
|
|
|
|
Indicates that the VCPU exits into userspace to process some tasks
|
|
related to Xen emulation.
|
|
|
|
Valid values for 'type' are:
|
|
|
|
- KVM_EXIT_XEN_HCALL -- synchronously notify user-space about Xen hypercall.
|
|
Userspace is expected to place the hypercall result into the appropriate
|
|
field before invoking KVM_RUN again.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_RISCV_SBI */
|
|
struct {
|
|
unsigned long extension_id;
|
|
unsigned long function_id;
|
|
unsigned long args[6];
|
|
unsigned long ret[2];
|
|
} riscv_sbi;
|
|
|
|
If exit reason is KVM_EXIT_RISCV_SBI then it indicates that the VCPU has
|
|
done a SBI call which is not handled by KVM RISC-V kernel module. The details
|
|
of the SBI call are available in 'riscv_sbi' member of kvm_run structure. The
|
|
'extension_id' field of 'riscv_sbi' represents SBI extension ID whereas the
|
|
'function_id' field represents function ID of given SBI extension. The 'args'
|
|
array field of 'riscv_sbi' represents parameters for the SBI call and 'ret'
|
|
array field represents return values. The userspace should update the return
|
|
values of SBI call before resuming the VCPU. For more details on RISC-V SBI
|
|
spec refer, https://github.com/riscv/riscv-sbi-doc.
|
|
|
|
::
|
|
|
|
/* KVM_EXIT_NOTIFY */
|
|
struct {
|
|
#define KVM_NOTIFY_CONTEXT_INVALID (1 << 0)
|
|
__u32 flags;
|
|
} notify;
|
|
|
|
Used on x86 systems. When the VM capability KVM_CAP_X86_NOTIFY_VMEXIT is
|
|
enabled, a VM exit generated if no event window occurs in VM non-root mode
|
|
for a specified amount of time. Once KVM_X86_NOTIFY_VMEXIT_USER is set when
|
|
enabling the cap, it would exit to userspace with the exit reason
|
|
KVM_EXIT_NOTIFY for further handling. The "flags" field contains more
|
|
detailed info.
|
|
|
|
The valid value for 'flags' is:
|
|
|
|
- KVM_NOTIFY_CONTEXT_INVALID -- the VM context is corrupted and not valid
|
|
in VMCS. It would run into unknown result if resume the target VM.
|
|
|
|
::
|
|
|
|
/* Fix the size of the union. */
|
|
char padding[256];
|
|
};
|
|
|
|
/*
|
|
* shared registers between kvm and userspace.
|
|
* kvm_valid_regs specifies the register classes set by the host
|
|
* kvm_dirty_regs specified the register classes dirtied by userspace
|
|
* struct kvm_sync_regs is architecture specific, as well as the
|
|
* bits for kvm_valid_regs and kvm_dirty_regs
|
|
*/
|
|
__u64 kvm_valid_regs;
|
|
__u64 kvm_dirty_regs;
|
|
union {
|
|
struct kvm_sync_regs regs;
|
|
char padding[SYNC_REGS_SIZE_BYTES];
|
|
} s;
|
|
|
|
If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access
|
|
certain guest registers without having to call SET/GET_*REGS. Thus we can
|
|
avoid some system call overhead if userspace has to handle the exit.
|
|
Userspace can query the validity of the structure by checking
|
|
kvm_valid_regs for specific bits. These bits are architecture specific
|
|
and usually define the validity of a groups of registers. (e.g. one bit
|
|
for general purpose registers)
|
|
|
|
Please note that the kernel is allowed to use the kvm_run structure as the
|
|
primary storage for certain register types. Therefore, the kernel may use the
|
|
values in kvm_run even if the corresponding bit in kvm_dirty_regs is not set.
|
|
|
|
::
|
|
|
|
};
|
|
|
|
|
|
|
|
6. Capabilities that can be enabled on vCPUs
|
|
============================================
|
|
|
|
There are certain capabilities that change the behavior of the virtual CPU or
|
|
the virtual machine when enabled. To enable them, please see section 4.37.
|
|
Below you can find a list of capabilities and what their effect on the vCPU or
|
|
the virtual machine is when enabling them.
|
|
|
|
The following information is provided along with the description:
|
|
|
|
Architectures:
|
|
which instruction set architectures provide this ioctl.
|
|
x86 includes both i386 and x86_64.
|
|
|
|
Target:
|
|
whether this is a per-vcpu or per-vm capability.
|
|
|
|
Parameters:
|
|
what parameters are accepted by the capability.
|
|
|
|
Returns:
|
|
the return value. General error numbers (EBADF, ENOMEM, EINVAL)
|
|
are not detailed, but errors with specific meanings are.
|
|
|
|
|
|
6.1 KVM_CAP_PPC_OSI
|
|
-------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: none
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability enables interception of OSI hypercalls that otherwise would
|
|
be treated as normal system calls to be injected into the guest. OSI hypercalls
|
|
were invented by Mac-on-Linux to have a standardized communication mechanism
|
|
between the guest and the host.
|
|
|
|
When this capability is enabled, KVM_EXIT_OSI can occur.
|
|
|
|
|
|
6.2 KVM_CAP_PPC_PAPR
|
|
--------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: none
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability enables interception of PAPR hypercalls. PAPR hypercalls are
|
|
done using the hypercall instruction "sc 1".
|
|
|
|
It also sets the guest privilege level to "supervisor" mode. Usually the guest
|
|
runs in "hypervisor" privilege mode with a few missing features.
|
|
|
|
In addition to the above, it changes the semantics of SDR1. In this mode, the
|
|
HTAB address part of SDR1 contains an HVA instead of a GPA, as PAPR keeps the
|
|
HTAB invisible to the guest.
|
|
|
|
When this capability is enabled, KVM_EXIT_PAPR_HCALL can occur.
|
|
|
|
|
|
6.3 KVM_CAP_SW_TLB
|
|
------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: args[0] is the address of a struct kvm_config_tlb
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
::
|
|
|
|
struct kvm_config_tlb {
|
|
__u64 params;
|
|
__u64 array;
|
|
__u32 mmu_type;
|
|
__u32 array_len;
|
|
};
|
|
|
|
Configures the virtual CPU's TLB array, establishing a shared memory area
|
|
between userspace and KVM. The "params" and "array" fields are userspace
|
|
addresses of mmu-type-specific data structures. The "array_len" field is an
|
|
safety mechanism, and should be set to the size in bytes of the memory that
|
|
userspace has reserved for the array. It must be at least the size dictated
|
|
by "mmu_type" and "params".
|
|
|
|
While KVM_RUN is active, the shared region is under control of KVM. Its
|
|
contents are undefined, and any modification by userspace results in
|
|
boundedly undefined behavior.
|
|
|
|
On return from KVM_RUN, the shared region will reflect the current state of
|
|
the guest's TLB. If userspace makes any changes, it must call KVM_DIRTY_TLB
|
|
to tell KVM which entries have been changed, prior to calling KVM_RUN again
|
|
on this vcpu.
|
|
|
|
For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_MMU_FSL_BOOKE_HV:
|
|
|
|
- The "params" field is of type "struct kvm_book3e_206_tlb_params".
|
|
- The "array" field points to an array of type "struct
|
|
kvm_book3e_206_tlb_entry".
|
|
- The array consists of all entries in the first TLB, followed by all
|
|
entries in the second TLB.
|
|
- Within a TLB, entries are ordered first by increasing set number. Within a
|
|
set, entries are ordered by way (increasing ESEL).
|
|
- The hash for determining set number in TLB0 is: (MAS2 >> 12) & (num_sets - 1)
|
|
where "num_sets" is the tlb_sizes[] value divided by the tlb_ways[] value.
|
|
- The tsize field of mas1 shall be set to 4K on TLB0, even though the
|
|
hardware ignores this value for TLB0.
|
|
|
|
6.4 KVM_CAP_S390_CSS_SUPPORT
|
|
----------------------------
|
|
|
|
:Architectures: s390
|
|
:Target: vcpu
|
|
:Parameters: none
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability enables support for handling of channel I/O instructions.
|
|
|
|
TEST PENDING INTERRUPTION and the interrupt portion of TEST SUBCHANNEL are
|
|
handled in-kernel, while the other I/O instructions are passed to userspace.
|
|
|
|
When this capability is enabled, KVM_EXIT_S390_TSCH will occur on TEST
|
|
SUBCHANNEL intercepts.
|
|
|
|
Note that even though this capability is enabled per-vcpu, the complete
|
|
virtual machine is affected.
|
|
|
|
6.5 KVM_CAP_PPC_EPR
|
|
-------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: args[0] defines whether the proxy facility is active
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability enables or disables the delivery of interrupts through the
|
|
external proxy facility.
|
|
|
|
When enabled (args[0] != 0), every time the guest gets an external interrupt
|
|
delivered, it automatically exits into user space with a KVM_EXIT_EPR exit
|
|
to receive the topmost interrupt vector.
|
|
|
|
When disabled (args[0] == 0), behavior is as if this facility is unsupported.
|
|
|
|
When this capability is enabled, KVM_EXIT_EPR can occur.
|
|
|
|
6.6 KVM_CAP_IRQ_MPIC
|
|
--------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: args[0] is the MPIC device fd;
|
|
args[1] is the MPIC CPU number for this vcpu
|
|
|
|
This capability connects the vcpu to an in-kernel MPIC device.
|
|
|
|
6.7 KVM_CAP_IRQ_XICS
|
|
--------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: args[0] is the XICS device fd;
|
|
args[1] is the XICS CPU number (server ID) for this vcpu
|
|
|
|
This capability connects the vcpu to an in-kernel XICS device.
|
|
|
|
6.8 KVM_CAP_S390_IRQCHIP
|
|
------------------------
|
|
|
|
:Architectures: s390
|
|
:Target: vm
|
|
:Parameters: none
|
|
|
|
This capability enables the in-kernel irqchip for s390. Please refer to
|
|
"4.24 KVM_CREATE_IRQCHIP" for details.
|
|
|
|
6.9 KVM_CAP_MIPS_FPU
|
|
--------------------
|
|
|
|
:Architectures: mips
|
|
:Target: vcpu
|
|
:Parameters: args[0] is reserved for future use (should be 0).
|
|
|
|
This capability allows the use of the host Floating Point Unit by the guest. It
|
|
allows the Config1.FP bit to be set to enable the FPU in the guest. Once this is
|
|
done the ``KVM_REG_MIPS_FPR_*`` and ``KVM_REG_MIPS_FCR_*`` registers can be
|
|
accessed (depending on the current guest FPU register mode), and the Status.FR,
|
|
Config5.FRE bits are accessible via the KVM API and also from the guest,
|
|
depending on them being supported by the FPU.
|
|
|
|
6.10 KVM_CAP_MIPS_MSA
|
|
---------------------
|
|
|
|
:Architectures: mips
|
|
:Target: vcpu
|
|
:Parameters: args[0] is reserved for future use (should be 0).
|
|
|
|
This capability allows the use of the MIPS SIMD Architecture (MSA) by the guest.
|
|
It allows the Config3.MSAP bit to be set to enable the use of MSA by the guest.
|
|
Once this is done the ``KVM_REG_MIPS_VEC_*`` and ``KVM_REG_MIPS_MSA_*``
|
|
registers can be accessed, and the Config5.MSAEn bit is accessible via the
|
|
KVM API and also from the guest.
|
|
|
|
6.74 KVM_CAP_SYNC_REGS
|
|
----------------------
|
|
|
|
:Architectures: s390, x86
|
|
:Target: s390: always enabled, x86: vcpu
|
|
:Parameters: none
|
|
:Returns: x86: KVM_CHECK_EXTENSION returns a bit-array indicating which register
|
|
sets are supported
|
|
(bitfields defined in arch/x86/include/uapi/asm/kvm.h).
|
|
|
|
As described above in the kvm_sync_regs struct info in section 5 (kvm_run):
|
|
KVM_CAP_SYNC_REGS "allow[s] userspace to access certain guest registers
|
|
without having to call SET/GET_*REGS". This reduces overhead by eliminating
|
|
repeated ioctl calls for setting and/or getting register values. This is
|
|
particularly important when userspace is making synchronous guest state
|
|
modifications, e.g. when emulating and/or intercepting instructions in
|
|
userspace.
|
|
|
|
For s390 specifics, please refer to the source code.
|
|
|
|
For x86:
|
|
|
|
- the register sets to be copied out to kvm_run are selectable
|
|
by userspace (rather that all sets being copied out for every exit).
|
|
- vcpu_events are available in addition to regs and sregs.
|
|
|
|
For x86, the 'kvm_valid_regs' field of struct kvm_run is overloaded to
|
|
function as an input bit-array field set by userspace to indicate the
|
|
specific register sets to be copied out on the next exit.
|
|
|
|
To indicate when userspace has modified values that should be copied into
|
|
the vCPU, the all architecture bitarray field, 'kvm_dirty_regs' must be set.
|
|
This is done using the same bitflags as for the 'kvm_valid_regs' field.
|
|
If the dirty bit is not set, then the register set values will not be copied
|
|
into the vCPU even if they've been modified.
|
|
|
|
Unused bitfields in the bitarrays must be set to zero.
|
|
|
|
::
|
|
|
|
struct kvm_sync_regs {
|
|
struct kvm_regs regs;
|
|
struct kvm_sregs sregs;
|
|
struct kvm_vcpu_events events;
|
|
};
|
|
|
|
6.75 KVM_CAP_PPC_IRQ_XIVE
|
|
-------------------------
|
|
|
|
:Architectures: ppc
|
|
:Target: vcpu
|
|
:Parameters: args[0] is the XIVE device fd;
|
|
args[1] is the XIVE CPU number (server ID) for this vcpu
|
|
|
|
This capability connects the vcpu to an in-kernel XIVE device.
|
|
|
|
7. Capabilities that can be enabled on VMs
|
|
==========================================
|
|
|
|
There are certain capabilities that change the behavior of the virtual
|
|
machine when enabled. To enable them, please see section 4.37. Below
|
|
you can find a list of capabilities and what their effect on the VM
|
|
is when enabling them.
|
|
|
|
The following information is provided along with the description:
|
|
|
|
Architectures:
|
|
which instruction set architectures provide this ioctl.
|
|
x86 includes both i386 and x86_64.
|
|
|
|
Parameters:
|
|
what parameters are accepted by the capability.
|
|
|
|
Returns:
|
|
the return value. General error numbers (EBADF, ENOMEM, EINVAL)
|
|
are not detailed, but errors with specific meanings are.
|
|
|
|
|
|
7.1 KVM_CAP_PPC_ENABLE_HCALL
|
|
----------------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: args[0] is the sPAPR hcall number;
|
|
args[1] is 0 to disable, 1 to enable in-kernel handling
|
|
|
|
This capability controls whether individual sPAPR hypercalls (hcalls)
|
|
get handled by the kernel or not. Enabling or disabling in-kernel
|
|
handling of an hcall is effective across the VM. On creation, an
|
|
initial set of hcalls are enabled for in-kernel handling, which
|
|
consists of those hcalls for which in-kernel handlers were implemented
|
|
before this capability was implemented. If disabled, the kernel will
|
|
not to attempt to handle the hcall, but will always exit to userspace
|
|
to handle it. Note that it may not make sense to enable some and
|
|
disable others of a group of related hcalls, but KVM does not prevent
|
|
userspace from doing that.
|
|
|
|
If the hcall number specified is not one that has an in-kernel
|
|
implementation, the KVM_ENABLE_CAP ioctl will fail with an EINVAL
|
|
error.
|
|
|
|
7.2 KVM_CAP_S390_USER_SIGP
|
|
--------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
This capability controls which SIGP orders will be handled completely in user
|
|
space. With this capability enabled, all fast orders will be handled completely
|
|
in the kernel:
|
|
|
|
- SENSE
|
|
- SENSE RUNNING
|
|
- EXTERNAL CALL
|
|
- EMERGENCY SIGNAL
|
|
- CONDITIONAL EMERGENCY SIGNAL
|
|
|
|
All other orders will be handled completely in user space.
|
|
|
|
Only privileged operation exceptions will be checked for in the kernel (or even
|
|
in the hardware prior to interception). If this capability is not enabled, the
|
|
old way of handling SIGP orders is used (partially in kernel and user space).
|
|
|
|
7.3 KVM_CAP_S390_VECTOR_REGISTERS
|
|
---------------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
:Returns: 0 on success, negative value on error
|
|
|
|
Allows use of the vector registers introduced with z13 processor, and
|
|
provides for the synchronization between host and user space. Will
|
|
return -EINVAL if the machine does not support vectors.
|
|
|
|
7.4 KVM_CAP_S390_USER_STSI
|
|
--------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
This capability allows post-handlers for the STSI instruction. After
|
|
initial handling in the kernel, KVM exits to user space with
|
|
KVM_EXIT_S390_STSI to allow user space to insert further data.
|
|
|
|
Before exiting to userspace, kvm handlers should fill in s390_stsi field of
|
|
vcpu->run::
|
|
|
|
struct {
|
|
__u64 addr;
|
|
__u8 ar;
|
|
__u8 reserved;
|
|
__u8 fc;
|
|
__u8 sel1;
|
|
__u16 sel2;
|
|
} s390_stsi;
|
|
|
|
@addr - guest address of STSI SYSIB
|
|
@fc - function code
|
|
@sel1 - selector 1
|
|
@sel2 - selector 2
|
|
@ar - access register number
|
|
|
|
KVM handlers should exit to userspace with rc = -EREMOTE.
|
|
|
|
7.5 KVM_CAP_SPLIT_IRQCHIP
|
|
-------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] - number of routes reserved for userspace IOAPICs
|
|
:Returns: 0 on success, -1 on error
|
|
|
|
Create a local apic for each processor in the kernel. This can be used
|
|
instead of KVM_CREATE_IRQCHIP if the userspace VMM wishes to emulate the
|
|
IOAPIC and PIC (and also the PIT, even though this has to be enabled
|
|
separately).
|
|
|
|
This capability also enables in kernel routing of interrupt requests;
|
|
when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type are
|
|
used in the IRQ routing table. The first args[0] MSI routes are reserved
|
|
for the IOAPIC pins. Whenever the LAPIC receives an EOI for these routes,
|
|
a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace.
|
|
|
|
Fails if VCPU has already been created, or if the irqchip is already in the
|
|
kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
|
|
|
|
7.6 KVM_CAP_S390_RI
|
|
-------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
Allows use of runtime-instrumentation introduced with zEC12 processor.
|
|
Will return -EINVAL if the machine does not support runtime-instrumentation.
|
|
Will return -EBUSY if a VCPU has already been created.
|
|
|
|
7.7 KVM_CAP_X2APIC_API
|
|
----------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] - features that should be enabled
|
|
:Returns: 0 on success, -EINVAL when args[0] contains invalid features
|
|
|
|
Valid feature flags in args[0] are::
|
|
|
|
#define KVM_X2APIC_API_USE_32BIT_IDS (1ULL << 0)
|
|
#define KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK (1ULL << 1)
|
|
|
|
Enabling KVM_X2APIC_API_USE_32BIT_IDS changes the behavior of
|
|
KVM_SET_GSI_ROUTING, KVM_SIGNAL_MSI, KVM_SET_LAPIC, and KVM_GET_LAPIC,
|
|
allowing the use of 32-bit APIC IDs. See KVM_CAP_X2APIC_API in their
|
|
respective sections.
|
|
|
|
KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK must be enabled for x2APIC to work
|
|
in logical mode or with more than 255 VCPUs. Otherwise, KVM treats 0xff
|
|
as a broadcast even in x2APIC mode in order to support physical x2APIC
|
|
without interrupt remapping. This is undesirable in logical mode,
|
|
where 0xff represents CPUs 0-7 in cluster 0.
|
|
|
|
7.8 KVM_CAP_S390_USER_INSTR0
|
|
----------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
With this capability enabled, all illegal instructions 0x0000 (2 bytes) will
|
|
be intercepted and forwarded to user space. User space can use this
|
|
mechanism e.g. to realize 2-byte software breakpoints. The kernel will
|
|
not inject an operating exception for these instructions, user space has
|
|
to take care of that.
|
|
|
|
This capability can be enabled dynamically even if VCPUs were already
|
|
created and are running.
|
|
|
|
7.9 KVM_CAP_S390_GS
|
|
-------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
:Returns: 0 on success; -EINVAL if the machine does not support
|
|
guarded storage; -EBUSY if a VCPU has already been created.
|
|
|
|
Allows use of guarded storage for the KVM guest.
|
|
|
|
7.10 KVM_CAP_S390_AIS
|
|
---------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
Allow use of adapter-interruption suppression.
|
|
:Returns: 0 on success; -EBUSY if a VCPU has already been created.
|
|
|
|
7.11 KVM_CAP_PPC_SMT
|
|
--------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: vsmt_mode, flags
|
|
|
|
Enabling this capability on a VM provides userspace with a way to set
|
|
the desired virtual SMT mode (i.e. the number of virtual CPUs per
|
|
virtual core). The virtual SMT mode, vsmt_mode, must be a power of 2
|
|
between 1 and 8. On POWER8, vsmt_mode must also be no greater than
|
|
the number of threads per subcore for the host. Currently flags must
|
|
be 0. A successful call to enable this capability will result in
|
|
vsmt_mode being returned when the KVM_CAP_PPC_SMT capability is
|
|
subsequently queried for the VM. This capability is only supported by
|
|
HV KVM, and can only be set before any VCPUs have been created.
|
|
The KVM_CAP_PPC_SMT_POSSIBLE capability indicates which virtual SMT
|
|
modes are available.
|
|
|
|
7.12 KVM_CAP_PPC_FWNMI
|
|
----------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: none
|
|
|
|
With this capability a machine check exception in the guest address
|
|
space will cause KVM to exit the guest with NMI exit reason. This
|
|
enables QEMU to build error log and branch to guest kernel registered
|
|
machine check handling routine. Without this capability KVM will
|
|
branch to guests' 0x200 interrupt vector.
|
|
|
|
7.13 KVM_CAP_X86_DISABLE_EXITS
|
|
------------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] defines which exits are disabled
|
|
:Returns: 0 on success, -EINVAL when args[0] contains invalid exits
|
|
|
|
Valid bits in args[0] are::
|
|
|
|
#define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0)
|
|
#define KVM_X86_DISABLE_EXITS_HLT (1 << 1)
|
|
#define KVM_X86_DISABLE_EXITS_PAUSE (1 << 2)
|
|
#define KVM_X86_DISABLE_EXITS_CSTATE (1 << 3)
|
|
|
|
Enabling this capability on a VM provides userspace with a way to no
|
|
longer intercept some instructions for improved latency in some
|
|
workloads, and is suggested when vCPUs are associated to dedicated
|
|
physical CPUs. More bits can be added in the future; userspace can
|
|
just pass the KVM_CHECK_EXTENSION result to KVM_ENABLE_CAP to disable
|
|
all such vmexits.
|
|
|
|
Do not enable KVM_FEATURE_PV_UNHALT if you disable HLT exits.
|
|
|
|
7.14 KVM_CAP_S390_HPAGE_1M
|
|
--------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
:Returns: 0 on success, -EINVAL if hpage module parameter was not set
|
|
or cmma is enabled, or the VM has the KVM_VM_S390_UCONTROL
|
|
flag set
|
|
|
|
With this capability the KVM support for memory backing with 1m pages
|
|
through hugetlbfs can be enabled for a VM. After the capability is
|
|
enabled, cmma can't be enabled anymore and pfmfi and the storage key
|
|
interpretation are disabled. If cmma has already been enabled or the
|
|
hpage module parameter is not set to 1, -EINVAL is returned.
|
|
|
|
While it is generally possible to create a huge page backed VM without
|
|
this capability, the VM will not be able to run.
|
|
|
|
7.15 KVM_CAP_MSR_PLATFORM_INFO
|
|
------------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] whether feature should be enabled or not
|
|
|
|
With this capability, a guest may read the MSR_PLATFORM_INFO MSR. Otherwise,
|
|
a #GP would be raised when the guest tries to access. Currently, this
|
|
capability does not enable write permissions of this MSR for the guest.
|
|
|
|
7.16 KVM_CAP_PPC_NESTED_HV
|
|
--------------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: none
|
|
:Returns: 0 on success, -EINVAL when the implementation doesn't support
|
|
nested-HV virtualization.
|
|
|
|
HV-KVM on POWER9 and later systems allows for "nested-HV"
|
|
virtualization, which provides a way for a guest VM to run guests that
|
|
can run using the CPU's supervisor mode (privileged non-hypervisor
|
|
state). Enabling this capability on a VM depends on the CPU having
|
|
the necessary functionality and on the facility being enabled with a
|
|
kvm-hv module parameter.
|
|
|
|
7.17 KVM_CAP_EXCEPTION_PAYLOAD
|
|
------------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] whether feature should be enabled or not
|
|
|
|
With this capability enabled, CR2 will not be modified prior to the
|
|
emulated VM-exit when L1 intercepts a #PF exception that occurs in
|
|
L2. Similarly, for kvm-intel only, DR6 will not be modified prior to
|
|
the emulated VM-exit when L1 intercepts a #DB exception that occurs in
|
|
L2. As a result, when KVM_GET_VCPU_EVENTS reports a pending #PF (or
|
|
#DB) exception for L2, exception.has_payload will be set and the
|
|
faulting address (or the new DR6 bits*) will be reported in the
|
|
exception_payload field. Similarly, when userspace injects a #PF (or
|
|
#DB) into L2 using KVM_SET_VCPU_EVENTS, it is expected to set
|
|
exception.has_payload and to put the faulting address - or the new DR6
|
|
bits\ [#]_ - in the exception_payload field.
|
|
|
|
This capability also enables exception.pending in struct
|
|
kvm_vcpu_events, which allows userspace to distinguish between pending
|
|
and injected exceptions.
|
|
|
|
|
|
.. [#] For the new DR6 bits, note that bit 16 is set iff the #DB exception
|
|
will clear DR6.RTM.
|
|
|
|
7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
|
|
|
|
:Architectures: x86, arm64, mips
|
|
:Parameters: args[0] whether feature should be enabled or not
|
|
|
|
Valid flags are::
|
|
|
|
#define KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE (1 << 0)
|
|
#define KVM_DIRTY_LOG_INITIALLY_SET (1 << 1)
|
|
|
|
With KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE is set, KVM_GET_DIRTY_LOG will not
|
|
automatically clear and write-protect all pages that are returned as dirty.
|
|
Rather, userspace will have to do this operation separately using
|
|
KVM_CLEAR_DIRTY_LOG.
|
|
|
|
At the cost of a slightly more complicated operation, this provides better
|
|
scalability and responsiveness for two reasons. First,
|
|
KVM_CLEAR_DIRTY_LOG ioctl can operate on a 64-page granularity rather
|
|
than requiring to sync a full memslot; this ensures that KVM does not
|
|
take spinlocks for an extended period of time. Second, in some cases a
|
|
large amount of time can pass between a call to KVM_GET_DIRTY_LOG and
|
|
userspace actually using the data in the page. Pages can be modified
|
|
during this time, which is inefficient for both the guest and userspace:
|
|
the guest will incur a higher penalty due to write protection faults,
|
|
while userspace can see false reports of dirty pages. Manual reprotection
|
|
helps reducing this time, improving guest performance and reducing the
|
|
number of dirty log false positives.
|
|
|
|
With KVM_DIRTY_LOG_INITIALLY_SET set, all the bits of the dirty bitmap
|
|
will be initialized to 1 when created. This also improves performance because
|
|
dirty logging can be enabled gradually in small chunks on the first call
|
|
to KVM_CLEAR_DIRTY_LOG. KVM_DIRTY_LOG_INITIALLY_SET depends on
|
|
KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE (it is also only available on
|
|
x86 and arm64 for now).
|
|
|
|
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 was previously available under the name
|
|
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT, but the implementation had bugs that make
|
|
it hard or impossible to use it correctly. The availability of
|
|
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 signals that those bugs are fixed.
|
|
Userspace should not try to use KVM_CAP_MANUAL_DIRTY_LOG_PROTECT.
|
|
|
|
7.19 KVM_CAP_PPC_SECURE_GUEST
|
|
------------------------------
|
|
|
|
:Architectures: ppc
|
|
|
|
This capability indicates that KVM is running on a host that has
|
|
ultravisor firmware and thus can support a secure guest. On such a
|
|
system, a guest can ask the ultravisor to make it a secure guest,
|
|
one whose memory is inaccessible to the host except for pages which
|
|
are explicitly requested to be shared with the host. The ultravisor
|
|
notifies KVM when a guest requests to become a secure guest, and KVM
|
|
has the opportunity to veto the transition.
|
|
|
|
If present, this capability can be enabled for a VM, meaning that KVM
|
|
will allow the transition to secure guest mode. Otherwise KVM will
|
|
veto the transition.
|
|
|
|
7.20 KVM_CAP_HALT_POLL
|
|
----------------------
|
|
|
|
:Architectures: all
|
|
:Target: VM
|
|
:Parameters: args[0] is the maximum poll time in nanoseconds
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability overrides the kvm module parameter halt_poll_ns for the
|
|
target VM.
|
|
|
|
VCPU polling allows a VCPU to poll for wakeup events instead of immediately
|
|
scheduling during guest halts. The maximum time a VCPU can spend polling is
|
|
controlled by the kvm module parameter halt_poll_ns. This capability allows
|
|
the maximum halt time to specified on a per-VM basis, effectively overriding
|
|
the module parameter for the target VM.
|
|
|
|
7.21 KVM_CAP_X86_USER_SPACE_MSR
|
|
-------------------------------
|
|
|
|
:Architectures: x86
|
|
:Target: VM
|
|
:Parameters: args[0] contains the mask of KVM_MSR_EXIT_REASON_* events to report
|
|
:Returns: 0 on success; -1 on error
|
|
|
|
This capability enables trapping of #GP invoking RDMSR and WRMSR instructions
|
|
into user space.
|
|
|
|
When a guest requests to read or write an MSR, KVM may not implement all MSRs
|
|
that are relevant to a respective system. It also does not differentiate by
|
|
CPU type.
|
|
|
|
To allow more fine grained control over MSR handling, user space may enable
|
|
this capability. With it enabled, MSR accesses that match the mask specified in
|
|
args[0] and trigger a #GP event inside the guest by KVM will instead trigger
|
|
KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR exit notifications which user space
|
|
can then handle to implement model specific MSR handling and/or user notifications
|
|
to inform a user that an MSR was not handled.
|
|
|
|
7.22 KVM_CAP_X86_BUS_LOCK_EXIT
|
|
-------------------------------
|
|
|
|
:Architectures: x86
|
|
:Target: VM
|
|
:Parameters: args[0] defines the policy used when bus locks detected in guest
|
|
:Returns: 0 on success, -EINVAL when args[0] contains invalid bits
|
|
|
|
Valid bits in args[0] are::
|
|
|
|
#define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
|
|
#define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
|
|
|
|
Enabling this capability on a VM provides userspace with a way to select
|
|
a policy to handle the bus locks detected in guest. Userspace can obtain
|
|
the supported modes from the result of KVM_CHECK_EXTENSION and define it
|
|
through the KVM_ENABLE_CAP.
|
|
|
|
KVM_BUS_LOCK_DETECTION_OFF and KVM_BUS_LOCK_DETECTION_EXIT are supported
|
|
currently and mutually exclusive with each other. More bits can be added in
|
|
the future.
|
|
|
|
With KVM_BUS_LOCK_DETECTION_OFF set, bus locks in guest will not cause vm exits
|
|
so that no additional actions are needed. This is the default mode.
|
|
|
|
With KVM_BUS_LOCK_DETECTION_EXIT set, vm exits happen when bus lock detected
|
|
in VM. KVM just exits to userspace when handling them. Userspace can enforce
|
|
its own throttling or other policy based mitigations.
|
|
|
|
This capability is aimed to address the thread that VM can exploit bus locks to
|
|
degree the performance of the whole system. Once the userspace enable this
|
|
capability and select the KVM_BUS_LOCK_DETECTION_EXIT mode, KVM will set the
|
|
KVM_RUN_BUS_LOCK flag in vcpu-run->flags field and exit to userspace. Concerning
|
|
the bus lock vm exit can be preempted by a higher priority VM exit, the exit
|
|
notifications to userspace can be KVM_EXIT_BUS_LOCK or other reasons.
|
|
KVM_RUN_BUS_LOCK flag is used to distinguish between them.
|
|
|
|
7.23 KVM_CAP_PPC_DAWR1
|
|
----------------------
|
|
|
|
:Architectures: ppc
|
|
:Parameters: none
|
|
:Returns: 0 on success, -EINVAL when CPU doesn't support 2nd DAWR
|
|
|
|
This capability can be used to check / enable 2nd DAWR feature provided
|
|
by POWER10 processor.
|
|
|
|
|
|
7.24 KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
|
|
-------------------------------------
|
|
|
|
Architectures: x86 SEV enabled
|
|
Type: vm
|
|
Parameters: args[0] is the fd of the source vm
|
|
Returns: 0 on success; ENOTTY on error
|
|
|
|
This capability enables userspace to copy encryption context from the vm
|
|
indicated by the fd to the vm this is called on.
|
|
|
|
This is intended to support in-guest workloads scheduled by the host. This
|
|
allows the in-guest workload to maintain its own NPTs and keeps the two vms
|
|
from accidentally clobbering each other with interrupts and the like (separate
|
|
APIC/MSRs/etc).
|
|
|
|
7.25 KVM_CAP_SGX_ATTRIBUTE
|
|
--------------------------
|
|
|
|
:Architectures: x86
|
|
:Target: VM
|
|
:Parameters: args[0] is a file handle of a SGX attribute file in securityfs
|
|
:Returns: 0 on success, -EINVAL if the file handle is invalid or if a requested
|
|
attribute is not supported by KVM.
|
|
|
|
KVM_CAP_SGX_ATTRIBUTE enables a userspace VMM to grant a VM access to one or
|
|
more priveleged enclave attributes. args[0] must hold a file handle to a valid
|
|
SGX attribute file corresponding to an attribute that is supported/restricted
|
|
by KVM (currently only PROVISIONKEY).
|
|
|
|
The SGX subsystem restricts access to a subset of enclave attributes to provide
|
|
additional security for an uncompromised kernel, e.g. use of the PROVISIONKEY
|
|
is restricted to deter malware from using the PROVISIONKEY to obtain a stable
|
|
system fingerprint. To prevent userspace from circumventing such restrictions
|
|
by running an enclave in a VM, KVM prevents access to privileged attributes by
|
|
default.
|
|
|
|
See Documentation/x86/sgx.rst for more details.
|
|
|
|
7.26 KVM_CAP_PPC_RPT_INVALIDATE
|
|
-------------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_RPT_INVALIDATE
|
|
:Architectures: ppc
|
|
:Type: vm
|
|
|
|
This capability indicates that the kernel is capable of handling
|
|
H_RPT_INVALIDATE hcall.
|
|
|
|
In order to enable the use of H_RPT_INVALIDATE in the guest,
|
|
user space might have to advertise it for the guest. For example,
|
|
IBM pSeries (sPAPR) guest starts using it if "hcall-rpt-invalidate" is
|
|
present in the "ibm,hypertas-functions" device-tree property.
|
|
|
|
This capability is enabled for hypervisors on platforms like POWER9
|
|
that support radix MMU.
|
|
|
|
7.27 KVM_CAP_EXIT_ON_EMULATION_FAILURE
|
|
--------------------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] whether the feature should be enabled or not
|
|
|
|
When this capability is enabled, an emulation failure will result in an exit
|
|
to userspace with KVM_INTERNAL_ERROR (except when the emulator was invoked
|
|
to handle a VMware backdoor instruction). Furthermore, KVM will now provide up
|
|
to 15 instruction bytes for any exit to userspace resulting from an emulation
|
|
failure. When these exits to userspace occur use the emulation_failure struct
|
|
instead of the internal struct. They both have the same layout, but the
|
|
emulation_failure struct matches the content better. It also explicitly
|
|
defines the 'flags' field which is used to describe the fields in the struct
|
|
that are valid (ie: if KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES is
|
|
set in the 'flags' field then both 'insn_size' and 'insn_bytes' have valid data
|
|
in them.)
|
|
|
|
7.28 KVM_CAP_ARM_MTE
|
|
--------------------
|
|
|
|
:Architectures: arm64
|
|
:Parameters: none
|
|
|
|
This capability indicates that KVM (and the hardware) supports exposing the
|
|
Memory Tagging Extensions (MTE) to the guest. It must also be enabled by the
|
|
VMM before creating any VCPUs to allow the guest access. Note that MTE is only
|
|
available to a guest running in AArch64 mode and enabling this capability will
|
|
cause attempts to create AArch32 VCPUs to fail.
|
|
|
|
When enabled the guest is able to access tags associated with any memory given
|
|
to the guest. KVM will ensure that the tags are maintained during swap or
|
|
hibernation of the host; however the VMM needs to manually save/restore the
|
|
tags as appropriate if the VM is migrated.
|
|
|
|
When this capability is enabled all memory in memslots must be mapped as
|
|
not-shareable (no MAP_SHARED), attempts to create a memslot with a
|
|
MAP_SHARED mmap will result in an -EINVAL return.
|
|
|
|
When enabled the VMM may make use of the ``KVM_ARM_MTE_COPY_TAGS`` ioctl to
|
|
perform a bulk copy of tags to/from the guest.
|
|
|
|
7.29 KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
|
|
-------------------------------------
|
|
|
|
Architectures: x86 SEV enabled
|
|
Type: vm
|
|
Parameters: args[0] is the fd of the source vm
|
|
Returns: 0 on success
|
|
|
|
This capability enables userspace to migrate the encryption context from the VM
|
|
indicated by the fd to the VM this is called on.
|
|
|
|
This is intended to support intra-host migration of VMs between userspace VMMs,
|
|
upgrading the VMM process without interrupting the guest.
|
|
|
|
7.30 KVM_CAP_PPC_AIL_MODE_3
|
|
-------------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_AIL_MODE_3
|
|
:Architectures: ppc
|
|
:Type: vm
|
|
|
|
This capability indicates that the kernel supports the mode 3 setting for the
|
|
"Address Translation Mode on Interrupt" aka "Alternate Interrupt Location"
|
|
resource that is controlled with the H_SET_MODE hypercall.
|
|
|
|
This capability allows a guest kernel to use a better-performance mode for
|
|
handling interrupts and system calls.
|
|
|
|
7.31 KVM_CAP_DISABLE_QUIRKS2
|
|
----------------------------
|
|
|
|
:Capability: KVM_CAP_DISABLE_QUIRKS2
|
|
:Parameters: args[0] - set of KVM quirks to disable
|
|
:Architectures: x86
|
|
:Type: vm
|
|
|
|
This capability, if enabled, will cause KVM to disable some behavior
|
|
quirks.
|
|
|
|
Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
|
|
quirks that can be disabled in KVM.
|
|
|
|
The argument to KVM_ENABLE_CAP for this capability is a bitmask of
|
|
quirks to disable, and must be a subset of the bitmask returned by
|
|
KVM_CHECK_EXTENSION.
|
|
|
|
The valid bits in cap.args[0] are:
|
|
|
|
=================================== ============================================
|
|
KVM_X86_QUIRK_LINT0_REENABLED By default, the reset value for the LVT
|
|
LINT0 register is 0x700 (APIC_MODE_EXTINT).
|
|
When this quirk is disabled, the reset value
|
|
is 0x10000 (APIC_LVT_MASKED).
|
|
|
|
KVM_X86_QUIRK_CD_NW_CLEARED By default, KVM clears CR0.CD and CR0.NW.
|
|
When this quirk is disabled, KVM does not
|
|
change the value of CR0.CD and CR0.NW.
|
|
|
|
KVM_X86_QUIRK_LAPIC_MMIO_HOLE By default, the MMIO LAPIC interface is
|
|
available even when configured for x2APIC
|
|
mode. When this quirk is disabled, KVM
|
|
disables the MMIO LAPIC interface if the
|
|
LAPIC is in x2APIC mode.
|
|
|
|
KVM_X86_QUIRK_OUT_7E_INC_RIP By default, KVM pre-increments %rip before
|
|
exiting to userspace for an OUT instruction
|
|
to port 0x7e. When this quirk is disabled,
|
|
KVM does not pre-increment %rip before
|
|
exiting to userspace.
|
|
|
|
KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this quirk is disabled, KVM sets
|
|
CPUID.01H:ECX[bit 3] (MONITOR/MWAIT) if
|
|
IA32_MISC_ENABLE[bit 18] (MWAIT) is set.
|
|
Additionally, when this quirk is disabled,
|
|
KVM clears CPUID.01H:ECX[bit 3] if
|
|
IA32_MISC_ENABLE[bit 18] is cleared.
|
|
|
|
KVM_X86_QUIRK_FIX_HYPERCALL_INSN By default, KVM rewrites guest
|
|
VMMCALL/VMCALL instructions to match the
|
|
vendor's hypercall instruction for the
|
|
system. When this quirk is disabled, KVM
|
|
will no longer rewrite invalid guest
|
|
hypercall instructions. Executing the
|
|
incorrect hypercall instruction will
|
|
generate a #UD within the guest.
|
|
|
|
KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By default, KVM emulates MONITOR/MWAIT (if
|
|
they are intercepted) as NOPs regardless of
|
|
whether or not MONITOR/MWAIT are supported
|
|
according to guest CPUID. When this quirk
|
|
is disabled and KVM_X86_DISABLE_EXITS_MWAIT
|
|
is not set (MONITOR/MWAIT are intercepted),
|
|
KVM will inject a #UD on MONITOR/MWAIT if
|
|
they're unsupported per guest CPUID. Note,
|
|
KVM will modify MONITOR/MWAIT support in
|
|
guest CPUID on writes to MISC_ENABLE if
|
|
KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT is
|
|
disabled.
|
|
=================================== ============================================
|
|
|
|
7.32 KVM_CAP_MAX_VCPU_ID
|
|
------------------------
|
|
|
|
:Architectures: x86
|
|
:Target: VM
|
|
:Parameters: args[0] - maximum APIC ID value set for current VM
|
|
:Returns: 0 on success, -EINVAL if args[0] is beyond KVM_MAX_VCPU_IDS
|
|
supported in KVM or if it has been set.
|
|
|
|
This capability allows userspace to specify maximum possible APIC ID
|
|
assigned for current VM session prior to the creation of vCPUs, saving
|
|
memory for data structures indexed by the APIC ID. Userspace is able
|
|
to calculate the limit to APIC ID values from designated
|
|
CPU topology.
|
|
|
|
The value can be changed only until KVM_ENABLE_CAP is set to a nonzero
|
|
value or until a vCPU is created. Upon creation of the first vCPU,
|
|
if the value was set to zero or KVM_ENABLE_CAP was not invoked, KVM
|
|
uses the return value of KVM_CHECK_EXTENSION(KVM_CAP_MAX_VCPU_ID) as
|
|
the maximum APIC ID.
|
|
|
|
7.33 KVM_CAP_X86_NOTIFY_VMEXIT
|
|
------------------------------
|
|
|
|
:Architectures: x86
|
|
:Target: VM
|
|
:Parameters: args[0] is the value of notify window as well as some flags
|
|
:Returns: 0 on success, -EINVAL if args[0] contains invalid flags or notify
|
|
VM exit is unsupported.
|
|
|
|
Bits 63:32 of args[0] are used for notify window.
|
|
Bits 31:0 of args[0] are for some flags. Valid bits are::
|
|
|
|
#define KVM_X86_NOTIFY_VMEXIT_ENABLED (1 << 0)
|
|
#define KVM_X86_NOTIFY_VMEXIT_USER (1 << 1)
|
|
|
|
This capability allows userspace to configure the notify VM exit on/off
|
|
in per-VM scope during VM creation. Notify VM exit is disabled by default.
|
|
When userspace sets KVM_X86_NOTIFY_VMEXIT_ENABLED bit in args[0], VMM will
|
|
enable this feature with the notify window provided, which will generate
|
|
a VM exit if no event window occurs in VM non-root mode for a specified of
|
|
time (notify window).
|
|
|
|
If KVM_X86_NOTIFY_VMEXIT_USER is set in args[0], upon notify VM exits happen,
|
|
KVM would exit to userspace for handling.
|
|
|
|
This capability is aimed to mitigate the threat that malicious VMs can
|
|
cause CPU stuck (due to event windows don't open up) and make the CPU
|
|
unavailable to host or other VMs.
|
|
|
|
8. Other capabilities.
|
|
======================
|
|
|
|
This section lists capabilities that give information about other
|
|
features of the KVM implementation.
|
|
|
|
8.1 KVM_CAP_PPC_HWRNG
|
|
---------------------
|
|
|
|
:Architectures: ppc
|
|
|
|
This capability, if KVM_CHECK_EXTENSION indicates that it is
|
|
available, means that the kernel has an implementation of the
|
|
H_RANDOM hypercall backed by a hardware random-number generator.
|
|
If present, the kernel H_RANDOM handler can be enabled for guest use
|
|
with the KVM_CAP_PPC_ENABLE_HCALL capability.
|
|
|
|
8.2 KVM_CAP_HYPERV_SYNIC
|
|
------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability, if KVM_CHECK_EXTENSION indicates that it is
|
|
available, means that the kernel has an implementation of the
|
|
Hyper-V Synthetic interrupt controller(SynIC). Hyper-V SynIC is
|
|
used to support Windows Hyper-V based guest paravirt drivers(VMBus).
|
|
|
|
In order to use SynIC, it has to be activated by setting this
|
|
capability via KVM_ENABLE_CAP ioctl on the vcpu fd. Note that this
|
|
will disable the use of APIC hardware virtualization even if supported
|
|
by the CPU, as it's incompatible with SynIC auto-EOI behavior.
|
|
|
|
8.3 KVM_CAP_PPC_RADIX_MMU
|
|
-------------------------
|
|
|
|
:Architectures: ppc
|
|
|
|
This capability, if KVM_CHECK_EXTENSION indicates that it is
|
|
available, means that the kernel can support guests using the
|
|
radix MMU defined in Power ISA V3.00 (as implemented in the POWER9
|
|
processor).
|
|
|
|
8.4 KVM_CAP_PPC_HASH_MMU_V3
|
|
---------------------------
|
|
|
|
:Architectures: ppc
|
|
|
|
This capability, if KVM_CHECK_EXTENSION indicates that it is
|
|
available, means that the kernel can support guests using the
|
|
hashed page table MMU defined in Power ISA V3.00 (as implemented in
|
|
the POWER9 processor), including in-memory segment tables.
|
|
|
|
8.5 KVM_CAP_MIPS_VZ
|
|
-------------------
|
|
|
|
:Architectures: mips
|
|
|
|
This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that
|
|
it is available, means that full hardware assisted virtualization capabilities
|
|
of the hardware are available for use through KVM. An appropriate
|
|
KVM_VM_MIPS_* type must be passed to KVM_CREATE_VM to create a VM which
|
|
utilises it.
|
|
|
|
If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is
|
|
available, it means that the VM is using full hardware assisted virtualization
|
|
capabilities of the hardware. This is useful to check after creating a VM with
|
|
KVM_VM_MIPS_DEFAULT.
|
|
|
|
The value returned by KVM_CHECK_EXTENSION should be compared against known
|
|
values (see below). All other values are reserved. This is to allow for the
|
|
possibility of other hardware assisted virtualization implementations which
|
|
may be incompatible with the MIPS VZ ASE.
|
|
|
|
== ==========================================================================
|
|
0 The trap & emulate implementation is in use to run guest code in user
|
|
mode. Guest virtual memory segments are rearranged to fit the guest in the
|
|
user mode address space.
|
|
|
|
1 The MIPS VZ ASE is in use, providing full hardware assisted
|
|
virtualization, including standard guest virtual memory segments.
|
|
== ==========================================================================
|
|
|
|
8.6 KVM_CAP_MIPS_TE
|
|
-------------------
|
|
|
|
:Architectures: mips
|
|
|
|
This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that
|
|
it is available, means that the trap & emulate implementation is available to
|
|
run guest code in user mode, even if KVM_CAP_MIPS_VZ indicates that hardware
|
|
assisted virtualisation is also available. KVM_VM_MIPS_TE (0) must be passed
|
|
to KVM_CREATE_VM to create a VM which utilises it.
|
|
|
|
If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is
|
|
available, it means that the VM is using trap & emulate.
|
|
|
|
8.7 KVM_CAP_MIPS_64BIT
|
|
----------------------
|
|
|
|
:Architectures: mips
|
|
|
|
This capability indicates the supported architecture type of the guest, i.e. the
|
|
supported register and address width.
|
|
|
|
The values returned when this capability is checked by KVM_CHECK_EXTENSION on a
|
|
kvm VM handle correspond roughly to the CP0_Config.AT register field, and should
|
|
be checked specifically against known values (see below). All other values are
|
|
reserved.
|
|
|
|
== ========================================================================
|
|
0 MIPS32 or microMIPS32.
|
|
Both registers and addresses are 32-bits wide.
|
|
It will only be possible to run 32-bit guest code.
|
|
|
|
1 MIPS64 or microMIPS64 with access only to 32-bit compatibility segments.
|
|
Registers are 64-bits wide, but addresses are 32-bits wide.
|
|
64-bit guest code may run but cannot access MIPS64 memory segments.
|
|
It will also be possible to run 32-bit guest code.
|
|
|
|
2 MIPS64 or microMIPS64 with access to all address segments.
|
|
Both registers and addresses are 64-bits wide.
|
|
It will be possible to run 64-bit or 32-bit guest code.
|
|
== ========================================================================
|
|
|
|
8.9 KVM_CAP_ARM_USER_IRQ
|
|
------------------------
|
|
|
|
:Architectures: arm64
|
|
|
|
This capability, if KVM_CHECK_EXTENSION indicates that it is available, means
|
|
that if userspace creates a VM without an in-kernel interrupt controller, it
|
|
will be notified of changes to the output level of in-kernel emulated devices,
|
|
which can generate virtual interrupts, presented to the VM.
|
|
For such VMs, on every return to userspace, the kernel
|
|
updates the vcpu's run->s.regs.device_irq_level field to represent the actual
|
|
output level of the device.
|
|
|
|
Whenever kvm detects a change in the device output level, kvm guarantees at
|
|
least one return to userspace before running the VM. This exit could either
|
|
be a KVM_EXIT_INTR or any other exit event, like KVM_EXIT_MMIO. This way,
|
|
userspace can always sample the device output level and re-compute the state of
|
|
the userspace interrupt controller. Userspace should always check the state
|
|
of run->s.regs.device_irq_level on every kvm exit.
|
|
The value in run->s.regs.device_irq_level can represent both level and edge
|
|
triggered interrupt signals, depending on the device. Edge triggered interrupt
|
|
signals will exit to userspace with the bit in run->s.regs.device_irq_level
|
|
set exactly once per edge signal.
|
|
|
|
The field run->s.regs.device_irq_level is available independent of
|
|
run->kvm_valid_regs or run->kvm_dirty_regs bits.
|
|
|
|
If KVM_CAP_ARM_USER_IRQ is supported, the KVM_CHECK_EXTENSION ioctl returns a
|
|
number larger than 0 indicating the version of this capability is implemented
|
|
and thereby which bits in run->s.regs.device_irq_level can signal values.
|
|
|
|
Currently the following bits are defined for the device_irq_level bitmap::
|
|
|
|
KVM_CAP_ARM_USER_IRQ >= 1:
|
|
|
|
KVM_ARM_DEV_EL1_VTIMER - EL1 virtual timer
|
|
KVM_ARM_DEV_EL1_PTIMER - EL1 physical timer
|
|
KVM_ARM_DEV_PMU - ARM PMU overflow interrupt signal
|
|
|
|
Future versions of kvm may implement additional events. These will get
|
|
indicated by returning a higher number from KVM_CHECK_EXTENSION and will be
|
|
listed above.
|
|
|
|
8.10 KVM_CAP_PPC_SMT_POSSIBLE
|
|
-----------------------------
|
|
|
|
:Architectures: ppc
|
|
|
|
Querying this capability returns a bitmap indicating the possible
|
|
virtual SMT modes that can be set using KVM_CAP_PPC_SMT. If bit N
|
|
(counting from the right) is set, then a virtual SMT mode of 2^N is
|
|
available.
|
|
|
|
8.11 KVM_CAP_HYPERV_SYNIC2
|
|
--------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability enables a newer version of Hyper-V Synthetic interrupt
|
|
controller (SynIC). The only difference with KVM_CAP_HYPERV_SYNIC is that KVM
|
|
doesn't clear SynIC message and event flags pages when they are enabled by
|
|
writing to the respective MSRs.
|
|
|
|
8.12 KVM_CAP_HYPERV_VP_INDEX
|
|
----------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that userspace can load HV_X64_MSR_VP_INDEX msr. Its
|
|
value is used to denote the target vcpu for a SynIC interrupt. For
|
|
compatibilty, KVM initializes this msr to KVM's internal vcpu index. When this
|
|
capability is absent, userspace can still query this msr's value.
|
|
|
|
8.13 KVM_CAP_S390_AIS_MIGRATION
|
|
-------------------------------
|
|
|
|
:Architectures: s390
|
|
:Parameters: none
|
|
|
|
This capability indicates if the flic device will be able to get/set the
|
|
AIS states for migration via the KVM_DEV_FLIC_AISM_ALL attribute and allows
|
|
to discover this without having to create a flic device.
|
|
|
|
8.14 KVM_CAP_S390_PSW
|
|
---------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that the PSW is exposed via the kvm_run structure.
|
|
|
|
8.15 KVM_CAP_S390_GMAP
|
|
----------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that the user space memory used as guest mapping can
|
|
be anywhere in the user memory address space, as long as the memory slots are
|
|
aligned and sized to a segment (1MB) boundary.
|
|
|
|
8.16 KVM_CAP_S390_COW
|
|
---------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that the user space memory used as guest mapping can
|
|
use copy-on-write semantics as well as dirty pages tracking via read-only page
|
|
tables.
|
|
|
|
8.17 KVM_CAP_S390_BPB
|
|
---------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that kvm will implement the interfaces to handle
|
|
reset, migration and nested KVM for branch prediction blocking. The stfle
|
|
facility 82 should not be provided to the guest without this capability.
|
|
|
|
8.18 KVM_CAP_HYPERV_TLBFLUSH
|
|
----------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that KVM supports paravirtualized Hyper-V TLB Flush
|
|
hypercalls:
|
|
HvFlushVirtualAddressSpace, HvFlushVirtualAddressSpaceEx,
|
|
HvFlushVirtualAddressList, HvFlushVirtualAddressListEx.
|
|
|
|
8.19 KVM_CAP_ARM_INJECT_SERROR_ESR
|
|
----------------------------------
|
|
|
|
:Architectures: arm64
|
|
|
|
This capability indicates that userspace can specify (via the
|
|
KVM_SET_VCPU_EVENTS ioctl) the syndrome value reported to the guest when it
|
|
takes a virtual SError interrupt exception.
|
|
If KVM advertises this capability, userspace can only specify the ISS field for
|
|
the ESR syndrome. Other parts of the ESR, such as the EC are generated by the
|
|
CPU when the exception is taken. If this virtual SError is taken to EL1 using
|
|
AArch64, this value will be reported in the ISS field of ESR_ELx.
|
|
|
|
See KVM_CAP_VCPU_EVENTS for more details.
|
|
|
|
8.20 KVM_CAP_HYPERV_SEND_IPI
|
|
----------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that KVM supports paravirtualized Hyper-V IPI send
|
|
hypercalls:
|
|
HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx.
|
|
|
|
8.21 KVM_CAP_HYPERV_DIRECT_TLBFLUSH
|
|
-----------------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that KVM running on top of Hyper-V hypervisor
|
|
enables Direct TLB flush for its guests meaning that TLB flush
|
|
hypercalls are handled by Level 0 hypervisor (Hyper-V) bypassing KVM.
|
|
Due to the different ABI for hypercall parameters between Hyper-V and
|
|
KVM, enabling this capability effectively disables all hypercall
|
|
handling by KVM (as some KVM hypercall may be mistakenly treated as TLB
|
|
flush hypercalls by Hyper-V) so userspace should disable KVM identification
|
|
in CPUID and only exposes Hyper-V identification. In this case, guest
|
|
thinks it's running on Hyper-V and only use Hyper-V hypercalls.
|
|
|
|
8.22 KVM_CAP_S390_VCPU_RESETS
|
|
-----------------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that the KVM_S390_NORMAL_RESET and
|
|
KVM_S390_CLEAR_RESET ioctls are available.
|
|
|
|
8.23 KVM_CAP_S390_PROTECTED
|
|
---------------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability indicates that the Ultravisor has been initialized and
|
|
KVM can therefore start protected VMs.
|
|
This capability governs the KVM_S390_PV_COMMAND ioctl and the
|
|
KVM_MP_STATE_LOAD MP_STATE. KVM_SET_MP_STATE can fail for protected
|
|
guests when the state change is invalid.
|
|
|
|
8.24 KVM_CAP_STEAL_TIME
|
|
-----------------------
|
|
|
|
:Architectures: arm64, x86
|
|
|
|
This capability indicates that KVM supports steal time accounting.
|
|
When steal time accounting is supported it may be enabled with
|
|
architecture-specific interfaces. This capability and the architecture-
|
|
specific interfaces must be consistent, i.e. if one says the feature
|
|
is supported, than the other should as well and vice versa. For arm64
|
|
see Documentation/virt/kvm/devices/vcpu.rst "KVM_ARM_VCPU_PVTIME_CTRL".
|
|
For x86 see Documentation/virt/kvm/x86/msr.rst "MSR_KVM_STEAL_TIME".
|
|
|
|
8.25 KVM_CAP_S390_DIAG318
|
|
-------------------------
|
|
|
|
:Architectures: s390
|
|
|
|
This capability enables a guest to set information about its control program
|
|
(i.e. guest kernel type and version). The information is helpful during
|
|
system/firmware service events, providing additional data about the guest
|
|
environments running on the machine.
|
|
|
|
The information is associated with the DIAGNOSE 0x318 instruction, which sets
|
|
an 8-byte value consisting of a one-byte Control Program Name Code (CPNC) and
|
|
a 7-byte Control Program Version Code (CPVC). The CPNC determines what
|
|
environment the control program is running in (e.g. Linux, z/VM...), and the
|
|
CPVC is used for information specific to OS (e.g. Linux version, Linux
|
|
distribution...)
|
|
|
|
If this capability is available, then the CPNC and CPVC can be synchronized
|
|
between KVM and userspace via the sync regs mechanism (KVM_SYNC_DIAG318).
|
|
|
|
8.26 KVM_CAP_X86_USER_SPACE_MSR
|
|
-------------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that KVM supports deflection of MSR reads and
|
|
writes to user space. It can be enabled on a VM level. If enabled, MSR
|
|
accesses that would usually trigger a #GP by KVM into the guest will
|
|
instead get bounced to user space through the KVM_EXIT_X86_RDMSR and
|
|
KVM_EXIT_X86_WRMSR exit notifications.
|
|
|
|
8.27 KVM_CAP_X86_MSR_FILTER
|
|
---------------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates that KVM supports that accesses to user defined MSRs
|
|
may be rejected. With this capability exposed, KVM exports new VM ioctl
|
|
KVM_X86_SET_MSR_FILTER which user space can call to specify bitmaps of MSR
|
|
ranges that KVM should reject access to.
|
|
|
|
In combination with KVM_CAP_X86_USER_SPACE_MSR, this allows user space to
|
|
trap and emulate MSRs that are outside of the scope of KVM as well as
|
|
limit the attack surface on KVM's MSR emulation code.
|
|
|
|
8.28 KVM_CAP_ENFORCE_PV_FEATURE_CPUID
|
|
-------------------------------------
|
|
|
|
Architectures: x86
|
|
|
|
When enabled, KVM will disable paravirtual features provided to the
|
|
guest according to the bits in the KVM_CPUID_FEATURES CPUID leaf
|
|
(0x40000001). Otherwise, a guest may use the paravirtual features
|
|
regardless of what has actually been exposed through the CPUID leaf.
|
|
|
|
8.29 KVM_CAP_DIRTY_LOG_RING
|
|
---------------------------
|
|
|
|
:Architectures: x86
|
|
:Parameters: args[0] - size of the dirty log ring
|
|
|
|
KVM is capable of tracking dirty memory using ring buffers that are
|
|
mmaped into userspace; there is one dirty ring per vcpu.
|
|
|
|
The dirty ring is available to userspace as an array of
|
|
``struct kvm_dirty_gfn``. Each dirty entry it's defined as::
|
|
|
|
struct kvm_dirty_gfn {
|
|
__u32 flags;
|
|
__u32 slot; /* as_id | slot_id */
|
|
__u64 offset;
|
|
};
|
|
|
|
The following values are defined for the flags field to define the
|
|
current state of the entry::
|
|
|
|
#define KVM_DIRTY_GFN_F_DIRTY BIT(0)
|
|
#define KVM_DIRTY_GFN_F_RESET BIT(1)
|
|
#define KVM_DIRTY_GFN_F_MASK 0x3
|
|
|
|
Userspace should call KVM_ENABLE_CAP ioctl right after KVM_CREATE_VM
|
|
ioctl to enable this capability for the new guest and set the size of
|
|
the rings. Enabling the capability is only allowed before creating any
|
|
vCPU, and the size of the ring must be a power of two. The larger the
|
|
ring buffer, the less likely the ring is full and the VM is forced to
|
|
exit to userspace. The optimal size depends on the workload, but it is
|
|
recommended that it be at least 64 KiB (4096 entries).
|
|
|
|
Just like for dirty page bitmaps, the buffer tracks writes to
|
|
all user memory regions for which the KVM_MEM_LOG_DIRTY_PAGES flag was
|
|
set in KVM_SET_USER_MEMORY_REGION. Once a memory region is registered
|
|
with the flag set, userspace can start harvesting dirty pages from the
|
|
ring buffer.
|
|
|
|
An entry in the ring buffer can be unused (flag bits ``00``),
|
|
dirty (flag bits ``01``) or harvested (flag bits ``1X``). The
|
|
state machine for the entry is as follows::
|
|
|
|
dirtied harvested reset
|
|
00 -----------> 01 -------------> 1X -------+
|
|
^ |
|
|
| |
|
|
+------------------------------------------+
|
|
|
|
To harvest the dirty pages, userspace accesses the mmaped ring buffer
|
|
to read the dirty GFNs. If the flags has the DIRTY bit set (at this stage
|
|
the RESET bit must be cleared), then it means this GFN is a dirty GFN.
|
|
The userspace should harvest this GFN and mark the flags from state
|
|
``01b`` to ``1Xb`` (bit 0 will be ignored by KVM, but bit 1 must be set
|
|
to show that this GFN is harvested and waiting for a reset), and move
|
|
on to the next GFN. The userspace should continue to do this until the
|
|
flags of a GFN have the DIRTY bit cleared, meaning that it has harvested
|
|
all the dirty GFNs that were available.
|
|
|
|
It's not necessary for userspace to harvest the all dirty GFNs at once.
|
|
However it must collect the dirty GFNs in sequence, i.e., the userspace
|
|
program cannot skip one dirty GFN to collect the one next to it.
|
|
|
|
After processing one or more entries in the ring buffer, userspace
|
|
calls the VM ioctl KVM_RESET_DIRTY_RINGS to notify the kernel about
|
|
it, so that the kernel will reprotect those collected GFNs.
|
|
Therefore, the ioctl must be called *before* reading the content of
|
|
the dirty pages.
|
|
|
|
The dirty ring can get full. When it happens, the KVM_RUN of the
|
|
vcpu will return with exit reason KVM_EXIT_DIRTY_LOG_FULL.
|
|
|
|
The dirty ring interface has a major difference comparing to the
|
|
KVM_GET_DIRTY_LOG interface in that, when reading the dirty ring from
|
|
userspace, it's still possible that the kernel has not yet flushed the
|
|
processor's dirty page buffers into the kernel buffer (with dirty bitmaps, the
|
|
flushing is done by the KVM_GET_DIRTY_LOG ioctl). To achieve that, one
|
|
needs to kick the vcpu out of KVM_RUN using a signal. The resulting
|
|
vmexit ensures that all dirty GFNs are flushed to the dirty rings.
|
|
|
|
NOTE: the capability KVM_CAP_DIRTY_LOG_RING and the corresponding
|
|
ioctl KVM_RESET_DIRTY_RINGS are mutual exclusive to the existing ioctls
|
|
KVM_GET_DIRTY_LOG and KVM_CLEAR_DIRTY_LOG. After enabling
|
|
KVM_CAP_DIRTY_LOG_RING with an acceptable dirty ring size, the virtual
|
|
machine will switch to ring-buffer dirty page tracking and further
|
|
KVM_GET_DIRTY_LOG or KVM_CLEAR_DIRTY_LOG ioctls will fail.
|
|
|
|
8.30 KVM_CAP_XEN_HVM
|
|
--------------------
|
|
|
|
:Architectures: x86
|
|
|
|
This capability indicates the features that Xen supports for hosting Xen
|
|
PVHVM guests. Valid flags are::
|
|
|
|
#define KVM_XEN_HVM_CONFIG_HYPERCALL_MSR (1 << 0)
|
|
#define KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL (1 << 1)
|
|
#define KVM_XEN_HVM_CONFIG_SHARED_INFO (1 << 2)
|
|
#define KVM_XEN_HVM_CONFIG_RUNSTATE (1 << 3)
|
|
#define KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL (1 << 4)
|
|
#define KVM_XEN_HVM_CONFIG_EVTCHN_SEND (1 << 5)
|
|
|
|
The KVM_XEN_HVM_CONFIG_HYPERCALL_MSR flag indicates that the KVM_XEN_HVM_CONFIG
|
|
ioctl is available, for the guest to set its hypercall page.
|
|
|
|
If KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL is also set, the same flag may also be
|
|
provided in the flags to KVM_XEN_HVM_CONFIG, without providing hypercall page
|
|
contents, to request that KVM generate hypercall page content automatically
|
|
and also enable interception of guest hypercalls with KVM_EXIT_XEN.
|
|
|
|
The KVM_XEN_HVM_CONFIG_SHARED_INFO flag indicates the availability of the
|
|
KVM_XEN_HVM_SET_ATTR, KVM_XEN_HVM_GET_ATTR, KVM_XEN_VCPU_SET_ATTR and
|
|
KVM_XEN_VCPU_GET_ATTR ioctls, as well as the delivery of exception vectors
|
|
for event channel upcalls when the evtchn_upcall_pending field of a vcpu's
|
|
vcpu_info is set.
|
|
|
|
The KVM_XEN_HVM_CONFIG_RUNSTATE flag indicates that the runstate-related
|
|
features KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR/_CURRENT/_DATA/_ADJUST are
|
|
supported by the KVM_XEN_VCPU_SET_ATTR/KVM_XEN_VCPU_GET_ATTR ioctls.
|
|
|
|
The KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL flag indicates that IRQ routing entries
|
|
of the type KVM_IRQ_ROUTING_XEN_EVTCHN are supported, with the priority
|
|
field set to indicate 2 level event channel delivery.
|
|
|
|
The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indicates that KVM supports
|
|
injecting event channel events directly into the guest with the
|
|
KVM_XEN_HVM_EVTCHN_SEND ioctl. It also indicates support for the
|
|
KVM_XEN_ATTR_TYPE_EVTCHN/XEN_VERSION HVM attributes and the
|
|
KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID/TIMER/UPCALL_VECTOR vCPU attributes.
|
|
related to event channel delivery, timers, and the XENVER_version
|
|
interception.
|
|
|
|
8.31 KVM_CAP_PPC_MULTITCE
|
|
-------------------------
|
|
|
|
:Capability: KVM_CAP_PPC_MULTITCE
|
|
:Architectures: ppc
|
|
:Type: vm
|
|
|
|
This capability means the kernel is capable of handling hypercalls
|
|
H_PUT_TCE_INDIRECT and H_STUFF_TCE without passing those into the user
|
|
space. This significantly accelerates DMA operations for PPC KVM guests.
|
|
User space should expect that its handlers for these hypercalls
|
|
are not going to be called if user space previously registered LIOBN
|
|
in KVM (via KVM_CREATE_SPAPR_TCE or similar calls).
|
|
|
|
In order to enable H_PUT_TCE_INDIRECT and H_STUFF_TCE use in the guest,
|
|
user space might have to advertise it for the guest. For example,
|
|
IBM pSeries (sPAPR) guest starts using them if "hcall-multi-tce" is
|
|
present in the "ibm,hypertas-functions" device-tree property.
|
|
|
|
The hypercalls mentioned above may or may not be processed successfully
|
|
in the kernel based fast path. If they can not be handled by the kernel,
|
|
they will get passed on to user space. So user space still has to have
|
|
an implementation for these despite the in kernel acceleration.
|
|
|
|
This capability is always enabled.
|
|
|
|
8.32 KVM_CAP_PTP_KVM
|
|
--------------------
|
|
|
|
:Architectures: arm64
|
|
|
|
This capability indicates that the KVM virtual PTP service is
|
|
supported in the host. A VMM can check whether the service is
|
|
available to the guest on migration.
|
|
|
|
8.33 KVM_CAP_HYPERV_ENFORCE_CPUID
|
|
---------------------------------
|
|
|
|
Architectures: x86
|
|
|
|
When enabled, KVM will disable emulated Hyper-V features provided to the
|
|
guest according to the bits Hyper-V CPUID feature leaves. Otherwise, all
|
|
currently implmented Hyper-V features are provided unconditionally when
|
|
Hyper-V identification is set in the HYPERV_CPUID_INTERFACE (0x40000001)
|
|
leaf.
|
|
|
|
8.34 KVM_CAP_EXIT_HYPERCALL
|
|
---------------------------
|
|
|
|
:Capability: KVM_CAP_EXIT_HYPERCALL
|
|
:Architectures: x86
|
|
:Type: vm
|
|
|
|
This capability, if enabled, will cause KVM to exit to userspace
|
|
with KVM_EXIT_HYPERCALL exit reason to process some hypercalls.
|
|
|
|
Calling KVM_CHECK_EXTENSION for this capability will return a bitmask
|
|
of hypercalls that can be configured to exit to userspace.
|
|
Right now, the only such hypercall is KVM_HC_MAP_GPA_RANGE.
|
|
|
|
The argument to KVM_ENABLE_CAP is also a bitmask, and must be a subset
|
|
of the result of KVM_CHECK_EXTENSION. KVM will forward to userspace
|
|
the hypercalls whose corresponding bit is in the argument, and return
|
|
ENOSYS for the others.
|
|
|
|
8.35 KVM_CAP_PMU_CAPABILITY
|
|
---------------------------
|
|
|
|
:Capability KVM_CAP_PMU_CAPABILITY
|
|
:Architectures: x86
|
|
:Type: vm
|
|
:Parameters: arg[0] is bitmask of PMU virtualization capabilities.
|
|
:Returns 0 on success, -EINVAL when arg[0] contains invalid bits
|
|
|
|
This capability alters PMU virtualization in KVM.
|
|
|
|
Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
|
|
PMU virtualization capabilities that can be adjusted on a VM.
|
|
|
|
The argument to KVM_ENABLE_CAP is also a bitmask and selects specific
|
|
PMU virtualization capabilities to be applied to the VM. This can
|
|
only be invoked on a VM prior to the creation of VCPUs.
|
|
|
|
At this time, KVM_PMU_CAP_DISABLE is the only capability. Setting
|
|
this capability will disable PMU virtualization for that VM. Usermode
|
|
should adjust CPUID leaf 0xA to reflect that the PMU is disabled.
|
|
|
|
8.36 KVM_CAP_ARM_SYSTEM_SUSPEND
|
|
-------------------------------
|
|
|
|
:Capability: KVM_CAP_ARM_SYSTEM_SUSPEND
|
|
:Architectures: arm64
|
|
:Type: vm
|
|
|
|
When enabled, KVM will exit to userspace with KVM_EXIT_SYSTEM_EVENT of
|
|
type KVM_SYSTEM_EVENT_SUSPEND to process the guest suspend request.
|
|
|
|
8.37 KVM_CAP_S390_PROTECTED_DUMP
|
|
--------------------------------
|
|
|
|
:Capability: KVM_CAP_S390_PROTECTED_DUMP
|
|
:Architectures: s390
|
|
:Type: vm
|
|
|
|
This capability indicates that KVM and the Ultravisor support dumping
|
|
PV guests. The `KVM_PV_DUMP` command is available for the
|
|
`KVM_S390_PV_COMMAND` ioctl and the `KVM_PV_INFO` command provides
|
|
dump related UV data. Also the vcpu ioctl `KVM_S390_PV_CPU_COMMAND` is
|
|
available and supports the `KVM_PV_DUMP_CPU` subcommand.
|
|
|
|
8.38 KVM_CAP_VM_DISABLE_NX_HUGE_PAGES
|
|
-------------------------------------
|
|
|
|
:Capability: KVM_CAP_VM_DISABLE_NX_HUGE_PAGES
|
|
:Architectures: x86
|
|
:Type: vm
|
|
:Parameters: arg[0] must be 0.
|
|
:Returns: 0 on success, -EPERM if the userspace process does not
|
|
have CAP_SYS_BOOT, -EINVAL if args[0] is not 0 or any vCPUs have been
|
|
created.
|
|
|
|
This capability disables the NX huge pages mitigation for iTLB MULTIHIT.
|
|
|
|
The capability has no effect if the nx_huge_pages module parameter is not set.
|
|
|
|
This capability may only be set before any vCPUs are created.
|
|
|
|
8.39 KVM_CAP_S390_CPU_TOPOLOGY
|
|
------------------------------
|
|
|
|
:Capability: KVM_CAP_S390_CPU_TOPOLOGY
|
|
:Architectures: s390
|
|
:Type: vm
|
|
|
|
This capability indicates that KVM will provide the S390 CPU Topology
|
|
facility which consist of the interpretation of the PTF instruction for
|
|
the function code 2 along with interception and forwarding of both the
|
|
PTF instruction with function codes 0 or 1 and the STSI(15,1,x)
|
|
instruction to the userland hypervisor.
|
|
|
|
The stfle facility 11, CPU Topology facility, should not be indicated
|
|
to the guest without this capability.
|
|
|
|
When this capability is present, KVM provides a new attribute group
|
|
on vm fd, KVM_S390_VM_CPU_TOPOLOGY.
|
|
This new attribute allows to get, set or clear the Modified Change
|
|
Topology Report (MTCR) bit of the SCA through the kvm_device_attr
|
|
structure.
|
|
|
|
When getting the Modified Change Topology Report value, the attr->addr
|
|
must point to a byte where the value will be stored or retrieved from.
|
|
|
|
9. Known KVM API problems
|
|
=========================
|
|
|
|
In some cases, KVM's API has some inconsistencies or common pitfalls
|
|
that userspace need to be aware of. This section details some of
|
|
these issues.
|
|
|
|
Most of them are architecture specific, so the section is split by
|
|
architecture.
|
|
|
|
9.1. x86
|
|
--------
|
|
|
|
``KVM_GET_SUPPORTED_CPUID`` issues
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
In general, ``KVM_GET_SUPPORTED_CPUID`` is designed so that it is possible
|
|
to take its result and pass it directly to ``KVM_SET_CPUID2``. This section
|
|
documents some cases in which that requires some care.
|
|
|
|
Local APIC features
|
|
~~~~~~~~~~~~~~~~~~~
|
|
|
|
CPU[EAX=1]:ECX[21] (X2APIC) is reported by ``KVM_GET_SUPPORTED_CPUID``,
|
|
but it can only be enabled if ``KVM_CREATE_IRQCHIP`` or
|
|
``KVM_ENABLE_CAP(KVM_CAP_IRQCHIP_SPLIT)`` are used to enable in-kernel emulation of
|
|
the local APIC.
|
|
|
|
The same is true for the ``KVM_FEATURE_PV_UNHALT`` paravirtualized feature.
|
|
|
|
CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by ``KVM_GET_SUPPORTED_CPUID``.
|
|
It can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER`` is present and the kernel
|
|
has enabled in-kernel emulation of the local APIC.
|
|
|
|
Obsolete ioctls and capabilities
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
KVM_CAP_DISABLE_QUIRKS does not let userspace know which quirks are actually
|
|
available. Use ``KVM_CHECK_EXTENSION(KVM_CAP_DISABLE_QUIRKS2)`` instead if
|
|
available.
|
|
|
|
Ordering of KVM_GET_*/KVM_SET_* ioctls
|
|
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
TBD
|