The diag 0x44 handler, which handles a directed yield, goes into a
a codepath that does a kvm_for_each_vcpu() and ultimately
deliverable_irqs(). The new check for kvm_s390_pv_cpu_is_protected()
contains an assertion that the vcpu->mutex is held, which isn't going
to be the case in this scenario.
The result is a plethora of these messages if the lock debugging
is enabled, and thus an implication that we have a problem.
WARNING: CPU: 9 PID: 16167 at arch/s390/kvm/kvm-s390.h:239 deliverable_irqs+0x1c6/0x1d0 [kvm]
...snip...
Call Trace:
[<000003ff80429bf2>] deliverable_irqs+0x1ca/0x1d0 [kvm]
([<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm])
[<000003ff8042ba82>] kvm_s390_vcpu_has_irq+0x2a/0xa8 [kvm]
[<000003ff804101e2>] kvm_arch_dy_runnable+0x22/0x38 [kvm]
[<000003ff80410284>] kvm_vcpu_on_spin+0x8c/0x1d0 [kvm]
[<000003ff80436888>] kvm_s390_handle_diag+0x3b0/0x768 [kvm]
[<000003ff80425af4>] kvm_handle_sie_intercept+0x1cc/0xcd0 [kvm]
[<000003ff80422bb0>] __vcpu_run+0x7b8/0xfd0 [kvm]
[<000003ff80423de6>] kvm_arch_vcpu_ioctl_run+0xee/0x3e0 [kvm]
[<000003ff8040ccd8>] kvm_vcpu_ioctl+0x2c8/0x8d0 [kvm]
[<00000001504ced06>] ksys_ioctl+0xae/0xe8
[<00000001504cedaa>] __s390x_sys_ioctl+0x2a/0x38
[<0000000150cb9034>] system_call+0xd8/0x2d8
2 locks held by CPU 2/KVM/16167:
#0: 00000001951980c0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x90/0x8d0 [kvm]
#1: 000000019599c0f0 (&kvm->srcu){....}, at: __vcpu_run+0x4bc/0xfd0 [kvm]
Last Breaking-Event-Address:
[<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm]
irq event stamp: 11967
hardirqs last enabled at (11975): [<00000001502992f2>] console_unlock+0x4ca/0x650
hardirqs last disabled at (11982): [<0000000150298ee8>] console_unlock+0xc0/0x650
softirqs last enabled at (7940): [<0000000150cba6ca>] __do_softirq+0x422/0x4d8
softirqs last disabled at (7929): [<00000001501cd688>] do_softirq_own_stack+0x70/0x80
Considering what's being done here, let's fix this by removing the
mutex assertion rather than acquiring the mutex for every other vcpu.
Fixes: 201ae986ea ("KVM: s390: protvirt: Implement interrupt injection")
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20200415190353.63625-1-farman@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Return the index of the last valid slot from gfn_to_memslot_approx() if
its binary search loop yielded an out-of-bounds index. The index can
be out-of-bounds if the specified gfn is less than the base of the
lowest memslot (which is also the last valid memslot).
Note, the sole caller, kvm_s390_get_cmma(), ensures used_slots is
non-zero.
Fixes: afdad61615 ("KVM: s390: Fix storage attributes migration with memory slots")
Cc: stable@vger.kernel.org # 4.19.x: 0774a964ef56: KVM: Fix out of range accesses to memslots
Cc: stable@vger.kernel.org # 4.19.x
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200408064059.8957-3-sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some bug fixes.
The new vdpa subsystem with two first drivers.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin:
- Some bug fixes
- The new vdpa subsystem with two first drivers
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM"
vdpa: move to drivers/vdpa
virtio: Intel IFC VF driver for VDPA
vdpasim: vDPA device simulator
vhost: introduce vDPA-based backend
virtio: introduce a vDPA based transport
vDPA: introduce vDPA bus
vringh: IOTLB support
vhost: factor out IOTLB
vhost: allow per device message handler
vhost: refine vhost and vringh kconfig
virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
virtio-net: Introduce hash report feature
virtio-net: Introduce RSS receive steering feature
virtio-net: Introduce extended RSC feature
tools/virtio: option to build an out of tree module
Whenever we get an -EFAULT, we failed to read in guest 2 physical
address space. Such addressing exceptions are reported via a program
intercept to the nested hypervisor.
We faked the intercept, we have to return to guest 2. Instead, right
now we would be returning -EFAULT from the intercept handler, eventually
crashing the VM.
the correct thing to do is to return 1 as rc == 1 is the internal
representation of "we have to go back into g2".
Addressing exceptions can only happen if the g2->g3 page tables
reference invalid g2 addresses (say, either a table or the final page is
not accessible - so something that basically never happens in sane
environments.
Identified by manual code inspection.
Fixes: a3508fbe9d ("KVM: s390: vsie: initial support for nested virtualization")
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200403153050.20569-3-david@redhat.com
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: fix patch description]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* GICv4.1 support
* 32bit host removal
PPC:
* secure (encrypted) using under the Protected Execution Framework
ultravisor
s390:
* allow disabling GISA (hardware interrupt injection) and protected
VMs/ultravisor support.
x86:
* New dirty bitmap flag that sets all bits in the bitmap when dirty
page logging is enabled; this is faster because it doesn't require bulk
modification of the page tables.
* Initial work on making nested SVM event injection more similar to VMX,
and less buggy.
* Various cleanups to MMU code (though the big ones and related
optimizations were delayed to 5.8). Instead of using cr3 in function
names which occasionally means eptp, KVM too has standardized on "pgd".
* A large refactoring of CPUID features, which now use an array that
parallels the core x86_features.
* Some removal of pointer chasing from kvm_x86_ops, which will also be
switched to static calls as soon as they are available.
* New Tigerlake CPUID features.
* More bugfixes, optimizations and cleanups.
Generic:
* selftests: cleanups, new MMU notifier stress test, steal-time test
* CSV output for kvm_stat.
KVM/MIPS has been broken since 5.5, it does not compile due to a patch committed
by MIPS maintainers. I had already prepared a fix, but the MIPS maintainers
prefer to fix it in generic code rather than KVM so they are taking care of it.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"ARM:
- GICv4.1 support
- 32bit host removal
PPC:
- secure (encrypted) using under the Protected Execution Framework
ultravisor
s390:
- allow disabling GISA (hardware interrupt injection) and protected
VMs/ultravisor support.
x86:
- New dirty bitmap flag that sets all bits in the bitmap when dirty
page logging is enabled; this is faster because it doesn't require
bulk modification of the page tables.
- Initial work on making nested SVM event injection more similar to
VMX, and less buggy.
- Various cleanups to MMU code (though the big ones and related
optimizations were delayed to 5.8). Instead of using cr3 in
function names which occasionally means eptp, KVM too has
standardized on "pgd".
- A large refactoring of CPUID features, which now use an array that
parallels the core x86_features.
- Some removal of pointer chasing from kvm_x86_ops, which will also
be switched to static calls as soon as they are available.
- New Tigerlake CPUID features.
- More bugfixes, optimizations and cleanups.
Generic:
- selftests: cleanups, new MMU notifier stress test, steal-time test
- CSV output for kvm_stat"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits)
x86/kvm: fix a missing-prototypes "vmread_error"
KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y
KVM: VMX: Add a trampoline to fix VMREAD error handling
KVM: SVM: Annotate svm_x86_ops as __initdata
KVM: VMX: Annotate vmx_x86_ops as __initdata
KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup()
KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection
KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes
KVM: VMX: Configure runtime hooks using vmx_x86_ops
KVM: VMX: Move hardware_setup() definition below vmx_x86_ops
KVM: x86: Move init-only kvm_x86_ops to separate struct
KVM: Pass kvm_init()'s opaque param to additional arch funcs
s390/gmap: return proper error code on ksm unsharing
KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move()
KVM: Fix out of range accesses to memslots
KVM: X86: Micro-optimize IPI fastpath delay
KVM: X86: Delay read msr data iff writes ICR MSR
KVM: PPC: Book3S HV: Add a capability for enabling secure guests
KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs
KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs
...
Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
not necessarily for VM since it's a generic userspace and kernel
communication protocol. Such dependency may prevent archs without
virtualization support from using vhost.
To solve this, a dedicated vhost menu is created under drivers so
CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.
While at it, also squash Kconfig.vringh into vhost Kconfig file. This
avoids the trick of conditional inclusion from VOP or CAIF. Then it
will be easier to introduce new vringh users and common dependency for
both vringh and vhost.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Pass @opaque to kvm_arch_hardware_setup() and
kvm_arch_check_processor_compat() to allow architecture specific code to
reference @opaque without having to stash it away in a temporary global
variable. This will enable x86 to separate its vendor specific callback
ops, which are passed via @opaque, into "init" and "runtime" ops without
having to stash away the "init" ops.
No functional change intended.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Cornelia Huck <cohuck@redhat.com> #s390
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200321202603.19355-2-sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- mark sie control block as 512 byte aligned
- use fallthrough;
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Merge tag 'kvm-s390-next-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: cleanups for 5.7
- mark sie control block as 512 byte aligned
- use fallthrough;
Reset the LRU slot if it becomes invalid when deleting a memslot to fix
an out-of-bounds/use-after-free access when searching through memslots.
Explicitly check for there being no used slots in search_memslots(), and
in the caller of s390's approximation variant.
Fixes: 36947254e5 ("KVM: Dynamically size memslot array based on number of used slots")
Reported-by: Qian Cai <cai@lca.pw>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200320205546.2396-2-sean.j.christopherson@intel.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1. Allow to disable gisa
2. protected virtual machines
Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
state like guest memory and guest registers anymore. Instead the
PVMs are mostly managed by a new entity called Ultravisor (UV),
which provides an API, so KVM and the PV can request management
actions.
PVMs are encrypted at rest and protected from hypervisor access
while running. They switch from a normal operation into protected
mode, so we can still use the standard boot process to load a
encrypted blob and then move it into protected mode.
Rebooting is only possible by passing through the unprotected/normal
mode and switching to protected again.
One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
add callbacks for inaccessible pages)
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Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
KVM: s390: Features and Enhancements for 5.7 part1
1. Allow to disable gisa
2. protected virtual machines
Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
state like guest memory and guest registers anymore. Instead the
PVMs are mostly managed by a new entity called Ultravisor (UV),
which provides an API, so KVM and the PV can request management
actions.
PVMs are encrypted at rest and protected from hypervisor access
while running. They switch from a normal operation into protected
mode, so we can still use the standard boot process to load a
encrypted blob and then move it into protected mode.
Rebooting is only possible by passing through the unprotected/normal
mode and switching to protected again.
One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
add callbacks for inaccessible pages)
Remove includes of asm/kvm_host.h from files that already include
linux/kvm_host.h to make it more obvious that there is no ordering issue
between the two headers. linux/kvm_host.h includes asm/kvm_host.h to
pick up architecture specific settings, and this will never change, i.e.
including asm/kvm_host.h after linux/kvm_host.h may seem problematic,
but in practice is simply redundant.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rework kvm_get_dirty_log() so that it "returns" the associated memslot
on success. A future patch will rework memslot handling such that
id_to_memslot() can return NULL, returning the memslot makes it more
obvious that the validity of the memslot has been verified, i.e.
precludes the need to add validity checks in the arch code that are
technically unnecessary.
To maintain ordering in s390, move the call to kvm_arch_sync_dirty_log()
from s390's kvm_vm_ioctl_get_dirty_log() to the new kvm_get_dirty_log().
This is a nop for PPC, the only other arch that doesn't select
KVM_GENERIC_DIRTYLOG_READ_PROTECT, as its sync_dirty_log() is empty.
Ideally, moving the sync_dirty_log() call would be done in a separate
patch, but it can't be done in a follow-on patch because that would
temporarily break s390's ordering. Making the move in a preparatory
patch would be functionally correct, but would create an odd scenario
where the moved sync_dirty_log() would operate on a "different" memslot
due to consuming the result of a different id_to_memslot(). The
memslot couldn't actually be different as slots_lock is held, but the
code is confusing enough as it is, i.e. moving sync_dirty_log() in this
patch is the lesser of all evils.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the implementations of KVM_GET_DIRTY_LOG and KVM_CLEAR_DIRTY_LOG
for CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT into common KVM code.
The arch specific implemenations are extremely similar, differing
only in whether the dirty log needs to be sync'd from hardware (x86)
and how the TLBs are flushed. Add new arch hooks to handle sync
and TLB flush; the sync will also be used for non-generic dirty log
support in a future patch (s390).
The ulterior motive for providing a common implementation is to
eliminate the dependency between arch and common code with respect to
the memslot referenced by the dirty log, i.e. to make it obvious in the
code that the validity of the memslot is guaranteed, as a future patch
will rework memslot handling such that id_to_memslot() can return NULL.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop the "const" attribute from @old in kvm_arch_commit_memory_region()
to allow arch specific code to free arch specific resources in the old
memslot without having to cast away the attribute. Freeing resources in
kvm_arch_commit_memory_region() paves the way for simplifying
kvm_free_memslot() by eliminating the last usage of its @dont param.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove kvm_arch_create_memslot() now that all arch implementations are
effectively nops. Removing kvm_arch_create_memslot() eliminates the
possibility for arch specific code to allocate memory prior to setting
a memslot, which sets the stage for simplifying kvm_free_memslot().
Cc: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When we do the initial CPU reset we must not only clear the registers
in the internal data structures but also in kvm_run sync_regs. For
modern userspace sync_regs is the only place that it looks at.
Fixes: 7de3f1423f ("KVM: s390: Add new reset vcpu API")
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The boolean module parameter "kvm.use_gisa" controls if newly
created guests will use the GISA facility if provided by the
host system. The default is yes.
# cat /sys/module/kvm/parameters/use_gisa
Y
The parameter can be changed on the fly.
# echo N > /sys/module/kvm/parameters/use_gisa
Already running guests are not affected by this change.
The kvm s390 debug feature shows if a guest is running with GISA.
# grep gisa /sys/kernel/debug/s390dbf/kvm-$pid/sprintf
00 01582725059:843303 3 - 08 00000000e119bc01 gisa 0x00000000c9ac2642 initialized
00 01582725059:903840 3 - 11 000000004391ee22 00[0000000000000000-0000000000000000]: AIV gisa format-1 enabled for cpu 000
...
00 01582725059:916847 3 - 08 0000000094fff572 gisa 0x00000000c9ac2642 cleared
In general, that value should not be changed as the GISA facility
enhances interruption delivery performance.
A reason to switch the GISA facility off might be a performance
comparison run or debugging.
Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Link: https://lore.kernel.org/r/20200227091031.102993-1-mimu@linux.ibm.com
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Now that everything is in place, we can announce the feature.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
For protected VMs, the VCPU resets are done by the Ultravisor, as KVM
has no access to the VCPU registers.
Note that the ultravisor will only accept a call for the exact reset
that has been requested.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
As PSW restart is handled by the ultravisor (and we only get a start
notification) we must re-check the PSW after a start before injecting
interrupts.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
We're not allowed to inject interrupts on intercepts that leave the
guest state in an "in-between" state where the next SIE entry will do a
continuation, namely secure instruction interception (104) and secure
prefix interception (112).
As our PSW is just a copy of the real one that will be replaced on the
next exit, we can mask out the interrupt bits in the PSW to make sure
that we do not inject anything.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Code 5 for the set cpu state UV call tells the UV to load a PSW from
the SE header (first IPL) or from guest location 0x0 (diag 308 subcode
0/1). Also it sets the cpu into operating state afterwards, so we can
start it.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
VCPU states have to be reported to the ultravisor for SIGP
interpretation, kdump, kexec and reboot.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diag 308 subcode 0 and 1 require several KVM and Ultravisor interactions.
Specific to these "soft" reboots are
* The "unshare all" UVC
* The "prepare for reset" UVC
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Only two program exceptions can be injected for a protected guest:
specification and operand.
For both, a code needs to be specified in the interrupt injection
control of the state description, as the guest prefix page is not
accessible to KVM for such guests.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
A lot of the registers are controlled by the Ultravisor and never
visible to KVM. Also some registers are overlayed, like gbea is with
sidad, which might leak data to userspace.
Hence we sync a minimal set of registers for both SIE formats and then
check and sync format 2 registers if necessary.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
For protected VMs the hypervisor can not access guest breaking event
address, program parameter, bpbc and todpr. Do not reset those fields
as the control block does not provide access to these fields.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
A lot of the registers are controlled by the Ultravisor and never
visible to KVM. Some fields in the sie control block are overlayed, like
gbea. As no known userspace uses the ONE_REG interface on s390 if sync
regs are available, no functionality is lost if it is disabled for
protected guests.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Save response to sidad and disable address checking for protected
guests.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
STHYI data has to go through the bounce buffer.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The current code tries to first pin shared pages, if that fails (e.g.
because the page is not shared) it will export them. For shared pages
this means that we get a new intercept telling us that the guest is
unsharing that page. We will unpin the page at that point in time,
following the same rules as for making a page secure (i.e. waiting for
writeback, no elevated page references, etc.)
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The SPX instruction is handled by the ultravisor. We do get a
notification intercept, though. Let us update our internal view.
In addition to that, when the guest prefix page is not secure, an
intercept 112 (0x70) is indicated. Let us make the prefix pages
secure again.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Now that we can't access guest memory anymore, we have a dedicated
satellite block that's a bounce buffer for instruction data.
We re-use the memop interface to copy the instruction data to / from
userspace. This lets us re-use a lot of QEMU code which used that
interface to make logical guest memory accesses which are not possible
anymore in protected mode anyway.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Guest registers for protected guests are stored at offset 0x380. We
will copy those to the usual places. Long term we could refactor this
or use register access functions.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
SIE intercept code 8 is used only on exception loops for protected
guests. That means we need to stop the guest when we see it. This is
done by userspace.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The sclp interrupt is kind of special. The ultravisor polices that we
do not inject an sclp interrupt with payload if no sccb is outstanding.
On the other hand we have "asynchronous" event interrupts, e.g. for
console input.
We separate both variants into sclp interrupt and sclp event interrupt.
The sclp interrupt is masked until a previous servc instruction has
finished (sie exit 108).
[frankja@linux.ibm.com: factoring out write_sclp]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This defines the necessary data structures in the SIE control block to
inject machine checks,external and I/O interrupts. We first define the
the interrupt injection control, which defines the next interrupt to
inject. Then we define the fields that contain the payload for machine
checks,external and I/O interrupts.
This is then used to implement interruption injection for the following
list of interruption types:
- I/O (uses inject io interruption)
__deliver_io
- External (uses inject external interruption)
__deliver_cpu_timer
__deliver_ckc
__deliver_emergency_signal
__deliver_external_call
- cpu restart (uses inject restart interruption)
__deliver_restart
- machine checks (uses mcic, failing address and external damage)
__write_machine_check
Please note that posted interrupts (GISA) are not used for protected
guests as of today.
The service interrupt is handled in a followup patch.
Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
We have two new SIE exit codes dealing with instructions.
104 (0x68) for a secure instruction interception, on which the SIE needs
hypervisor action to complete the instruction. We can piggy-back on the
existing instruction handlers.
108 which is merely a notification and provides data for tracking and
management. For example this is used to tell the host about a new value
for the prefix register. As there will be several special case handlers
in later patches, we handle this in a separate function.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Since there is no interception for load control and load psw
instruction in the protected mode, we need a new way to get notified
whenever we can inject an IRQ right after the guest has just enabled
the possibility for receiving them.
The new interception codes solve that problem by providing a
notification for changes to IRQ enablement relevant bits in CRs 0, 6
and 14, as well a the machine check mask bit in the PSW.
No special handling is needed for these interception codes, the KVM
pre-run code will consult all necessary CRs and PSW bits and inject
IRQs the guest is enabled for.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Before we destroy the secure configuration, we better make all
pages accessible again. This also happens during reboot, where we reboot
into a non-secure guest that then can go again into secure mode. As
this "new" secure guest will have a new ID we cannot reuse the old page
state.
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>
KSM will not work on secure pages, because when the kernel reads a
secure page, it will be encrypted and hence no two pages will look the
same.
Let's mark the guest pages as unmergeable when we transition to secure
mode.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This contains 3 main changes:
1. changes in SIE control block handling for secure guests
2. helper functions for create/destroy/unpack secure guests
3. KVM_S390_PV_COMMAND ioctl to allow userspace dealing with secure
machines
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Let's have some debug traces which stay around for longer than the
guest.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The adapter interrupt page containing the indicator bits is currently
pinned. That means that a guest with many devices can pin a lot of
memory pages in the host. This also complicates the reference tracking
which is needed for memory management handling of protected virtual
machines. It might also have some strange side effects for madvise
MADV_DONTNEED and other things.
We can simply try to get the userspace page set the bits and free the
page. By storing the userspace address in the irq routing entry instead
of the guest address we can actually avoid many lookups and list walks
so that this variant is very likely not slower.
If userspace messes around with the memory slots the worst thing that
can happen is that we write to some other memory within that process.
As we get the the page with FOLL_WRITE this can also not be used to
write to shared read-only pages.
Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[borntraeger@de.ibm.com: patch simplification]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The architecture states that we need to reset local IRQs for all CPU
resets. Because the old reset interface did not support the normal CPU
reset we never did that on a normal reset.
Let's implement an interface for the missing normal and clear resets
and reset all local IRQs, registers and control structures as stated
in the architecture.
Userspace might already reset the registers via the vcpu run struct,
but as we need the interface for the interrupt clearing part anyway,
we implement the resets fully and don't rely on userspace to reset the
rest.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-4-frankja@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
The code seems to be quite old and uses lots of unneeded spaces for
alignment, which doesn't really help with readability.
Let's:
* Get rid of the extra spaces
* Remove the ULs as they are not needed on 0s
* Define constants for the CR 0 and 14 initial values
* Use the sizeof of the gcr array to memset it to 0
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20200131100205.74720-3-frankja@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Paolo Bonzini