Commit Graph

419 Commits

Author SHA1 Message Date
Vitaly Kuznetsov 2ddc649810 KVM: fix KVM_CAP_HYPERV_TLBFLUSH paragraph number
KVM_CAP_HYPERV_TLBFLUSH collided with KVM_CAP_S390_PSW-BPB, its paragraph
number should now be 8.18.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-06-22 17:30:20 +02:00
Liran Alon 71e9d9aeec KVM: docs: nVMX: Remove known limitations as they do not exist now
We can document other "Known Limitations" but the ones currently
referenced don't hold anymore...

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:28 +02:00
Liran Alon 7f4693b8bb KVM: docs: mmu: KVM support exposing SLAT to guests
Fix outdated statement that KVM is not able to expose SLAT
(Second-Layer-Address-Translation) to guests.
This was implemented a long time ago...

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 19:18:27 +02:00
Paolo Bonzini 5eec43a1fa KVM/ARM updates for 4.18
- Lazy context-switching of FPSIMD registers on arm64
 - Allow virtual redistributors to be part of two or more MMIO ranges
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Merge tag 'kvmarm-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.18

- Lazy context-switching of FPSIMD registers on arm64
- Allow virtual redistributors to be part of two or more MMIO ranges
2018-06-01 19:17:22 +02:00
Liran Alon 75025cc9d1 KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:37:34 +02:00
Jim Mattson df9cb9cc5b kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation
Document the subtle nuances that KVM_CAP_X86_DISABLE_EXITS induces in
the KVM_GET_SUPPORTED_CPUID API.

Fixes: 4d5422cea3 ("KVM: X86: Provide a capability to disable MWAIT intercepts")
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:37:34 +02:00
Vitaly Kuznetsov c1aea9196e KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability
We need a new capability to indicate support for the newly added
HvFlushVirtualAddress{List,Space}{,Ex} hypercalls. Upon seeing this
capability, userspace is supposed to announce PV TLB flush features
by setting the appropriate CPUID bits (if needed).

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-26 15:35:35 +02:00
Eric Auger d6c77bd19c KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION
We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in
KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the
base address and size of a redistributor region

Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows
to declare several separate redistributor regions.

So the whole redist space does not need to be contiguous anymore.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-05-25 12:29:26 +01:00
Michael S. Tsirkin 633711e828 kvm: rename KVM_HINTS_DEDICATED to KVM_HINTS_REALTIME
KVM_HINTS_DEDICATED seems to be somewhat confusing:

Guest doesn't really care whether it's the only task running on a host
CPU as long as it's not preempted.

And there are more reasons for Guest to be preempted than host CPU
sharing, for example, with memory overcommit it can get preempted on a
memory access, post copy migration can cause preemption, etc.

Let's call it KVM_HINTS_REALTIME which seems to better
match what guests expect.

Also, the flag most be set on all vCPUs - current guests assume this.
Note so in the documentation.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-17 19:12:13 +02:00
Marc Zyngier 85bd0ba1ff arm/arm64: KVM: Add PSCI version selection API
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.

But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.

This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.

Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-04-20 16:32:23 +01:00
Andrew Jones 21e94acaaa KVM: trivial documentation cleanups
Add missing entries to the index and ensure the entries are in
alphabetical order. Also amd-memory-encryption.rst is an .rst
not a .txt.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-28 22:47:06 +02:00
Wanpeng Li caa057a2ca KVM: X86: Provide a capability to disable HLT intercepts
If host CPUs are dedicated to a VM, we can avoid VM exits on HLT.
This patch adds the per-VM capability to disable them.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16 22:03:52 +01:00
Wanpeng Li 4d5422cea3 KVM: X86: Provide a capability to disable MWAIT intercepts
Allowing a guest to execute MWAIT without interception enables a guest
to put a (physical) CPU into a power saving state, where it takes
longer to return from than what may be desired by the host.

Don't give a guest that power over a host by default. (Especially,
since nothing prevents a guest from using MWAIT even when it is not
advertised via CPUID.)

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16 22:03:51 +01:00
Paolo Bonzini 4956aa3b8b KVM: s390: fixes and features
- more kvm stat counters
 - virtio gpu plumbing. The 3 non-KVM/s390 patches have Acks from
   Bartlomiej Zolnierkiewicz, Heiko Carstens and Greg Kroah-Hartman
   but all belong together to make virtio-gpu work as a tty. So
   I carried them in the KVM/s390 tree.
 - document some KVM_CAPs
 - cpu-model only facilities
 - cleanups
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Merge tag 'kvm-s390-next-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: fixes and features

- more kvm stat counters
- virtio gpu plumbing. The 3 non-KVM/s390 patches have Acks from
  Bartlomiej Zolnierkiewicz, Heiko Carstens and Greg Kroah-Hartman
  but all belong together to make virtio-gpu work as a tty. So
  I carried them in the KVM/s390 tree.
- document some KVM_CAPs
- cpu-model only facilities
- cleanups
2018-03-16 22:03:18 +01:00
Christian Borntraeger 5c2b4d5b78 KVM: document KVM_CAP_S390_[BPB|PSW|GMAP|COW]
commit 35b3fde620 ("KVM: s390: wire up bpb feature") has no
documentation for KVM_CAP_S390_BPB. While adding this let's also add
other missing capabilities like KVM_CAP_S390_PSW, KVM_CAP_S390_GMAP and
KVM_CAP_S390_COW.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-03-14 19:21:06 +00:00
Wanpeng Li a4429e53c9 KVM: Introduce paravirtualization hints and KVM_HINTS_DEDICATED
This patch introduces kvm_para_has_hint() to query for hints about
the configuration of the guests.  The first hint KVM_HINTS_DEDICATED,
is set if the guest has dedicated physical CPUs for each vCPU (i.e.
pinning and no over-commitment).  This allows optimizing spinlocks
and tells the guest to avoid PV TLB flush.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:44 +01:00
Ken Hofsass 01643c51bf KVM: x86: KVM_CAP_SYNC_REGS
This commit implements an enhanced x86 version of S390
KVM_CAP_SYNC_REGS functionality. KVM_CAP_SYNC_REGS "allow[s]
userspace to access certain guest registers without having
to call SET/GET_*REGS”. This reduces ioctl overhead which
is particularly important when userspace is making synchronous
guest state modifications (e.g. when emulating and/or intercepting
instructions).

Originally implemented upstream for the S390, the x86 differences
follow:
- userspace can select the register sets to be synchronized with kvm_run
using bit-flags in the kvm_valid_registers and kvm_dirty_registers
fields.
- vcpu_events is available in addition to the regs and sregs register
sets.

Signed-off-by: Ken Hofsass <hofsass@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Removed wrapper around check for reserved kvm_valid_regs. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:43 +01:00
Ken Hofsass 7b7e39522a KVM: x86: add SYNC_REGS_SIZE_BYTES #define.
Replace hardcoded padding size value for struct kvm_sync_regs
with #define SYNC_REGS_SIZE_BYTES.

Also update the value specified in api.txt from outdated hardcoded
value to SYNC_REGS_SIZE_BYTES.

Signed-off-by: Ken Hofsass <hofsass@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:43 +01:00
Roman Kagan faeb7833ee kvm: x86: hyperv: guest->host event signaling via eventfd
In Hyper-V, the fast guest->host notification mechanism is the
SIGNAL_EVENT hypercall, with a single parameter of the connection ID to
signal.

Currently this hypercall incurs a user exit and requires the userspace
to decode the parameters and trigger the notification of the potentially
different I/O context.

To avoid the costly user exit, process this hypercall and signal the
corresponding eventfd in KVM, similar to ioeventfd.  The association
between the connection id and the eventfd is established via the newly
introduced KVM_HYPERV_EVENTFD ioctl, and maintained in an
(srcu-protected) IDR.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[asm/hyperv.h changes approved by KY Srinivasan. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-06 18:40:36 +01:00
Tom Lendacky 801e459a6f KVM: x86: Add a framework for supporting MSR-based features
Provide a new KVM capability that allows bits within MSRs to be recognized
as features.  Two new ioctls are added to the /dev/kvm ioctl routine to
retrieve the list of these MSRs and then retrieve their values. A kvm_x86_ops
callback is used to determine support for the listed MSR-based features.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Tweaked documentation. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-01 19:00:28 +01:00
Radim Krčmář fe2a3027e7 KVM: x86: fix backward migration with async_PF
Guests on new hypersiors might set KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT
bit when enabling async_PF, but this bit is reserved on old hypervisors,
which results in a failure upon migration.

To avoid breaking different cases, we are checking for CPUID feature bit
before enabling the feature and nothing else.

Fixes: 52a5c155cf ("KVM: async_pf: Let guest support delivery of async_pf from guest mode")
Cc: <stable@vger.kernel.org>
Reviewed-by: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-02-24 01:43:48 +01:00
Radim Krčmář d2b9b2079e PPC KVM update for 4.16
- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs
   without requiring the complex thread synchronization that earlier
   CPU versions required.
 
 - A series from Ben Herrenschmidt to improve the handling of
   escalation interrupts with the XIVE interrupt controller.
 
 - Provide for the decrementer register to be copied across on
   migration.
 
 - Various minor cleanups and bugfixes.
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Merge tag 'kvm-ppc-next-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

PPC KVM update for 4.16

- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs
  without requiring the complex thread synchronization that earlier
  CPU versions required.

- A series from Ben Herrenschmidt to improve the handling of
  escalation interrupts with the XIVE interrupt controller.

- Provide for the decrementer register to be copied across on
  migration.

- Various minor cleanups and bugfixes.
2018-02-01 16:13:07 +01:00
Radim Krčmář 7bf14c28ee Merge branch 'x86/hyperv' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Topic branch for stable KVM clockource under Hyper-V.

Thanks to Christoffer Dall for resolving the ARM conflict.
2018-02-01 15:04:17 +01:00
Radim Krčmář e53175395d KVM/ARM Changes for v4.16
The changes for this version include icache invalidation optimizations
 (improving VM startup time), support for forwarded level-triggered
 interrupts (improved performance for timers and passthrough platform
 devices), a small fix for power-management notifiers, and some cosmetic
 changes.
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Merge tag 'kvm-arm-for-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

KVM/ARM Changes for v4.16

The changes for this version include icache invalidation optimizations
(improving VM startup time), support for forwarded level-triggered
interrupts (improved performance for timers and passthrough platform
devices), a small fix for power-management notifiers, and some cosmetic
changes.
2018-01-31 13:34:41 +01:00
Paul Mackerras 3214d01f13 KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds
This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace
information about the underlying machine's level of vulnerability
to the recently announced vulnerabilities CVE-2017-5715,
CVE-2017-5753 and CVE-2017-5754, and whether the machine provides
instructions to assist software to work around the vulnerabilities.

The ioctl returns two u64 words describing characteristics of the
CPU and required software behaviour respectively, plus two mask
words which indicate which bits have been filled in by the kernel,
for extensibility.  The bit definitions are the same as for the
new H_GET_CPU_CHARACTERISTICS hypercall.

There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which
indicates whether the new ioctl is available.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-19 15:17:01 +11:00
Paul Mackerras d27998185d Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the ppc-kvm topic branch of the powerpc tree to get
two patches which are prerequisites for the following patch series,
plus another patch which touches both powerpc and KVM code.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-19 12:09:57 +11:00
Paolo Bonzini 65e38583c3 Merge branch 'sev-v9-p2' of https://github.com/codomania/kvm
This part of Secure Encrypted Virtualization (SEV) patch series focuses on KVM
changes required to create and manage SEV guests.

SEV is an extension to the AMD-V architecture which supports running encrypted
virtual machine (VMs) under the control of a hypervisor. Encrypted VMs have their
pages (code and data) secured such that only the guest itself has access to
unencrypted version. Each encrypted VM is associated with a unique encryption key;
if its data is accessed to a different entity using a different key the encrypted
guest's data will be incorrectly decrypted, leading to unintelligible data.
This security model ensures that hypervisor will no longer able to inspect or
alter any guest code or data.

The key management of this feature is handled by a separate processor known as
the AMD Secure Processor (AMD-SP) which is present on AMD SOCs. The SEV Key
Management Specification (see below) provides a set of commands which can be
used by hypervisor to load virtual machine keys through the AMD-SP driver.

The patch series adds a new ioctl in KVM driver (KVM_MEMORY_ENCRYPT_OP). The
ioctl will be used by qemu to issue SEV guest-specific commands defined in Key
Management Specification.

The following links provide additional details:

AMD Memory Encryption white paper:
http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf

AMD64 Architecture Programmer's Manual:
    http://support.amd.com/TechDocs/24593.pdf
    SME is section 7.10
    SEV is section 15.34

SEV Key Management:
http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf

KVM Forum Presentation:
http://www.linux-kvm.org/images/7/74/02x08A-Thomas_Lendacky-AMDs_Virtualizatoin_Memory_Encryption_Technology.pdf

SEV Guest BIOS support:
  SEV support has been add to EDKII/OVMF BIOS
  https://github.com/tianocore/edk2

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-16 16:35:32 +01:00
Wanpeng Li 858a43aae2 KVM: X86: use paravirtualized TLB Shootdown
Remote TLB flush does a busy wait which is fine in bare-metal
scenario. But with-in the guest, the vcpus might have been pre-empted or
blocked. In this scenario, the initator vcpu would end up busy-waiting
for a long amount of time; it also consumes CPU unnecessarily to wake
up the target of the shootdown.

This patch set adds support for KVM's new paravirtualized TLB flush;
remote TLB flush does not wait for vcpus that are sleeping, instead
KVM will flush the TLB as soon as the vCPU starts running again.

The improvement is clearly visible when the host is overcommitted; in this
case, the PV TLB flush (in addition to avoiding the wait on the main CPU)
prevents preempted vCPUs from stealing precious execution time from the
running ones.

Testing on a Xeon Gold 6142 2.6GHz 2 sockets, 32 cores, 64 threads,
so 64 pCPUs, and each VM is 64 vCPUs.

ebizzy -M
              vanilla    optimized     boost
1VM            46799       48670         4%
2VM            23962       42691        78%
3VM            16152       37539       132%

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-01-16 16:34:13 +01:00
Paul Mackerras 5855564c8a KVM: PPC: Book3S HV: Enable migration of decrementer register
This adds a register identifier for use with the one_reg interface
to allow the decrementer expiry time to be read and written by
userspace.  The decrementer expiry time is in guest timebase units
and is equal to the sum of the decrementer and the guest timebase.
(The expiry time is used rather than the decrementer value itself
because the expiry time is not constantly changing, though the
decrementer value is, while the guest vcpu is not running.)

Without this, a guest vcpu migrated to a new host will see its
decrementer set to some random value.  On POWER8 and earlier, the
decrementer is 32 bits wide and counts down at 512MHz, so the
guest vcpu will potentially see no decrementer interrupts for up
to about 4 seconds, which will lead to a stall.  With POWER9, the
decrementer is now 56 bits side, so the stall can be much longer
(up to 2.23 years) and more noticeable.

To help work around the problem in cases where userspace has not been
updated to migrate the decrementer expiry time, we now set the
default decrementer expiry at vcpu creation time to the current time
rather than the maximum possible value.  This should mean an
immediate decrementer interrupt when a migrated vcpu starts
running.  In cases where the decrementer is 32 bits wide and more
than 4 seconds elapse between the creation of the vcpu and when it
first runs, the decrementer would have wrapped around to positive
values and there may still be a stall - but this is no worse than
the current situation.  In the large-decrementer case, we are sure
to get an immediate decrementer interrupt (assuming the time from
vcpu creation to first run is less than 2.23 years) and we thus
avoid a very long stall.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-01-16 11:54:45 +11:00
Christoffer Dall e5a2cfb492 KVM: arm/arm64: Delete outdated forwarded irq documentation
The reason I added this documentation originally was that the concept of
"never taking the interrupt", but just use the timer to generate an exit
from the guest, was confusing to most, and we had to explain it several
times over.  But as we can clearly see, we've failed to update the
documentation as the code has evolved, and people who need to understand
these details are probably better off reading the code.

Let's lighten our maintenance burden slightly and just get rid of this.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02 10:05:46 +01:00
Christian Borntraeger bb64da9aba KVM: s390: mark irq_state.flags as non-usable
Old kernels did not check for zero in the irq_state.flags field and old
QEMUs did not zero the flag/reserved fields when calling
KVM_S390_*_IRQ_STATE.  Let's add comments to prevent future uses of
these fields.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-12-06 09:18:43 +01:00
Brijesh Singh dc48bae01e KVM: Define SEV key management command id
Define Secure Encrypted Virtualization (SEV) key management command id
and structure. The command definition is available in SEV KM spec
0.14 (http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf)
and Documentation/virtual/kvm/amd-memory-encryption.txt.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:21:53 -06:00
Brijesh Singh 69eaedee41 KVM: Introduce KVM_MEMORY_ENCRYPT_{UN,}REG_REGION ioctl
If hardware supports memory encryption then KVM_MEMORY_ENCRYPT_REG_REGION
and KVM_MEMORY_ENCRYPT_UNREG_REGION ioctl's can be used by userspace to
register/unregister the guest memory regions which may contain the encrypted
data (e.g guest RAM, PCI BAR, SMRAM etc).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:26 -06:00
Brijesh Singh 5acc5c0631 KVM: Introduce KVM_MEMORY_ENCRYPT_OP ioctl
If the hardware supports memory encryption then the
KVM_MEMORY_ENCRYPT_OP ioctl can be used by qemu to issue a platform
specific memory encryption commands.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:26 -06:00
Brijesh Singh b38defdb44 Documentation/virtual/kvm: Add AMD Secure Encrypted Virtualization (SEV)
Create a Documentation entry to describe the AMD Secure Encrypted
Virtualization (SEV) feature.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: kvm@vger.kernel.org
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:23 -06:00
Paolo Bonzini fc3790fa07 GICv4 Support for KVM/ARM for v4.15
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Merge tag 'kvm-arm-gicv4-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

GICv4 Support for KVM/ARM for v4.15
2017-11-17 13:20:01 +01:00
Radim Krčmář a6014f1ab7 KVM: s390: fixes and improvements for 4.15
- Some initial preparation patches for exitless interrupts and crypto
 - New capability for AIS migration
 - Fixes
 - merge of the sthyi tree from the base s390 team, which moves the sthyi
 out of KVM into a shared function also for non-KVM
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Merge tag 'kvm-s390-next-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux

KVM: s390: fixes and improvements for 4.15

- Some initial preparation patches for exitless interrupts and crypto
- New capability for AIS migration
- Fixes
- merge of the sthyi tree from the base s390 team, which moves the sthyi
out of KVM into a shared function also for non-KVM
2017-11-16 14:39:46 +01:00
Marc Zyngier bd94e7aea4 KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved
The GICv4 architecture doesn't make it easy for save/restore to
work, as it doesn't give any guarantee that the pending state
is written into the pending table.

So let's not take any chance, and let's return an error if
we encounter any LPI that has the HW bit set. In order for
userspace to distinguish this error from other failure modes,
use -EACCES as an error code.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-10 09:44:36 +01:00
Christian Borntraeger da9a1446d2 KVM: s390: provide a capability for AIS state migration
The AIS capability was introduced in 4.12, while the interface to
migrate the state was added in 4.13. Unfortunately it is not possible
for userspace to detect the migration capability without creating a flic
kvm device. As in QEMU the cpu model detection runs on the "none"
machine this will result in cpu model issues regarding the "ais"
capability.

To get the "ais" capability properly let's add a new KVM capability that
tells userspace that AIS states can be migrated.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com>
2017-11-09 16:48:51 +01:00
Michael Mueller 4dd6f17eb9 KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
There is a chance to delete not yet delivered I/O interrupts if an
exploiter uses the subsystem identification word 0x0000 while
processing a KVM_DEV_FLIC_CLEAR_IO_IRQ ioctl. -EINVAL will be returned
now instead in that case.

Classic interrupts will always have bit 0x10000 set in the schid while
adapter interrupts have a zero schid. The clear_io_irq interface is
only useful for classic interrupts (as adapter interrupts belong to
many devices). Let's make this interface more strict and forbid a schid
of 0.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-11-09 09:49:48 +01:00
Radim Krčmář f0d438e4fb KVM/ARM Changes for v4.15
Changes include:
  - Optimized arch timer handling for KVM/ARM
  - Improvements to the VGIC ITS code and introduction of an ITS reset
    ioctl
  - Unification of the 32-bit fault injection logic
  - More exact external abort matching logic
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Merge tag 'kvm-arm-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into next

KVM/ARM Changes for v4.15

Changes include:
 - Optimized arch timer handling for KVM/ARM
 - Improvements to the VGIC ITS code and introduction of an ITS reset
   ioctl
 - Unification of the 32-bit fault injection logic
 - More exact external abort matching logic
2017-11-08 15:28:34 +01:00
Eric Auger ae204f80ca KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET
At the moment, the in-kernel emulated ITS is not properly reset.
On guest restart/reset some registers keep their old values and
internal structures like device, ITE, and collection lists are not
freed.

This may lead to various bugs. Among them, we can have incorrect state
backup or failure when saving the ITS state at early guest boot stage.

This patch documents a new attribute, KVM_DEV_ARM_ITS_CTRL_RESET in
the KVM_DEV_ARM_VGIC_GRP_CTRL group.

Upon this action, we can reset registers and especially those
pointing to tables previously allocated by the guest and free
the internal data structures storing the list of devices, collections
and lpis.

The usual approach for device reset of having userspace write
the reset values of the registers to the kernel via the register
read/write APIs doesn't work for the ITS because it has some
internal state (caches) which is not exposed as registers,
and there is no register interface for "drop cached data without
writing it back to RAM". So we need a KVM API which mimics the
hardware's reset line, to provide the equivalent behaviour to
a "pull the power cord out of the back of the machine" reset.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: wanghaibin <wanghaibin.wang@huawei.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-06 16:23:19 +01:00
David Hildenbrand 1af1ac910b KVM: x86: allow setting identity map addr with no vcpus only
Changing it afterwards doesn't make too much sense and will only result
in inconsistencies.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-12 14:01:53 +02:00
David Hildenbrand 726b99c4f7 KVM: x86: document special identity map address value
Setting it to 0 leads to setting it to the default value, let's document
this.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-12 14:01:53 +02:00
Radim Krčmář 082d3900a4 KVM/ARM Changes for v4.14
Two minor cleanups and improvements, a fix for decoding external abort
 types from guests, and added support for migrating the active priority
 of interrupts when running a GICv2 guest on a GICv3 host.
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Merge tag 'kvm-arm-for-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm

KVM/ARM Changes for v4.14

Two minor cleanups and improvements, a fix for decoding external abort
types from guests, and added support for migrating the active priority
of interrupts when running a GICv2 guest on a GICv3 host.
2017-09-07 18:22:04 +02:00
Christoffer Dall 9b87e7a8bf KVM: arm/arm64: Support uaccess of GICC_APRn
When migrating guests around we need to know the active priorities to
ensure functional virtual interrupt prioritization by the GIC.

This commit clarifies the API and how active priorities of interrupts in
different groups are represented, and implements the accessor functions
for the uaccess register range.

We live with a slight layering violation in accessing GICv3 data
structures from vgic-mmio-v2.c, because anything else just adds too much
complexity for us to deal with (it's not like there's a benefit
elsewhere in the code of an intermediate representation as is the case
with the VMCR).  We accept this, because while doing v3 processing from
a file named something-v2.c can look strange at first, this really is
specific to dealing with the user space interface for something that
looks like a GICv2.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-09-05 17:33:39 +02:00
Collin L. Walling 8fa1696ea7 KVM: s390: Multiple Epoch Facility support
Allow for the enablement of MEF and the support for the extended
epoch in SIE and VSIE for the extended guest TOD-Clock.

A new interface is used for getting/setting a guest's extended TOD-Clock
that uses a single ioctl invocation, KVM_S390_VM_TOD_EXT.  Since the
host time is a moving target that might see an epoch switch or STP sync
checks we need an atomic ioctl and cannot use the exisiting two
interfaces. The old method of getting and setting the guest TOD-Clock is
still retained and is used when the old ioctls are called.

Signed-off-by: Collin L. Walling <walling@linux.vnet.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-08-29 15:15:54 +02:00
Roman Kagan d3457c877b kvm: x86: hyperv: make VP_INDEX managed by userspace
Hyper-V identifies vCPUs by Virtual Processor Index, which can be
queried via HV_X64_MSR_VP_INDEX msr.  It is defined by the spec as a
sequential number which can't exceed the maximum number of vCPUs per VM.
APIC ids can be sparse and thus aren't a valid replacement for VP
indices.

Current KVM uses its internal vcpu index as VP_INDEX.  However, to make
it predictable and persistent across VM migrations, the userspace has to
control the value of VP_INDEX.

This patch achieves that, by storing vp_index explicitly on vcpu, and
allowing HV_X64_MSR_VP_INDEX to be set from the host side.  For
compatibility it's initialized to KVM vcpu index.  Also a few variables
are renamed to make clear distinction betweed this Hyper-V vp_index and
KVM vcpu_id (== APIC id).  Besides, a new capability,
KVM_CAP_HYPERV_VP_INDEX, is added to allow the userspace to skip
attempting msr writes where unsupported, to avoid spamming error logs.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-14 16:28:18 +02:00
Wanpeng Li 52a5c155cf KVM: async_pf: Let guest support delivery of async_pf from guest mode
Adds another flag bit (bit 2) to MSR_KVM_ASYNC_PF_EN. If bit 2 is 1,
async page faults are delivered to L1 as #PF vmexits; if bit 2 is 0,
kvm_can_do_async_pf returns 0 if in guest mode.

This is similar to what svm.c wanted to do all along, but it is only
enabled for Linux as L1 hypervisor.  Foreign hypervisors must never
receive async page faults as vmexits, because they'd probably be very
confused about that.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-14 14:26:16 +02:00
Roman Kagan efc479e690 kvm: x86: hyperv: add KVM_CAP_HYPERV_SYNIC2
There is a flaw in the Hyper-V SynIC implementation in KVM: when message
page or event flags page is enabled by setting the corresponding msr,
KVM zeroes it out.  This is problematic because on migration the
corresponding MSRs are loaded on the destination, so the content of
those pages is lost.

This went unnoticed so far because the only user of those pages was
in-KVM hyperv synic timers, which could continue working despite that
zeroing.

Newer QEMU uses those pages for Hyper-V VMBus implementation, and
zeroing them breaks the migration.

Besides, in newer QEMU the content of those pages is fully managed by
QEMU, so zeroing them is undesirable even when writing the MSRs from the
guest side.

To support this new scheme, introduce a new capability,
KVM_CAP_HYPERV_SYNIC2, which, when enabled, makes sure that the synic
pages aren't zeroed out in KVM.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-13 17:41:04 +02:00