| 0de1020f | 23-May-2026 |
Kevin Cheng <chengkev@google.com> |
KVM: selftests: Add nested page fault injection test
Add a test that exercises nested page fault injection during L2
execution. L2 executes I/O string instructions (OUTSB/INSB) that access
memory re
KVM: selftests: Add nested page fault injection test
Add a test that exercises nested page fault injection during L2
execution. L2 executes I/O string instructions (OUTSB/INSB) that access
memory restricted in L1's nested page tables (NPT/EPT), triggering a
nested page fault that L0 must inject to L1.
The test supports both AMD SVM (NPF) and Intel VMX (EPT violation) and
verifies that:
- The exit reason is an NPF/EPT violation
- The access type and permission bits are correct
- The faulting GPA is correct
Three test cases are implemented:
- Unmap the final data page (final translation fault, OUTSB read)
- Unmap a PT page (page walk fault, OUTSB read)
- Write-protect the final data page (protection violation, INSB write)
- Write-protect a PT page (protection violation on A/D update, OUTSB
read)
Signed-off-by: Kevin Cheng <chengkev@google.com>
[sean: name it nested_tdp_fault_test, consolidate asserts]
Link: https://patch.msgid.link/20260522232701.3671446-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| dfd2a8b0 | 20-Apr-2026 |
Sean Christopherson <seanjc@google.com> |
KVM: selftests: Replace "paddr" with "gpa" throughout
Replace all variations of "paddr" variables in KVM selftests with "gpa",
with the exception of the ELF structures, as those fields are not speci
KVM: selftests: Replace "paddr" with "gpa" throughout
Replace all variations of "paddr" variables in KVM selftests with "gpa",
with the exception of the ELF structures, as those fields are not specific
to guest virtual addresses, to complete the conversion from vm_paddr_t to
gpa_t.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-20-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| abc37419 | 20-Apr-2026 |
Sean Christopherson <seanjc@google.com> |
KVM: selftests: Replace "u64 nested_paddr" with "gpa_t l2_gpa"
In x86's nested TDP APIs, use the appropriate gpa_t typedef and rename
variables from nested_paddr to l2_gpa to match KVM x86's nomencl
KVM: selftests: Replace "u64 nested_paddr" with "gpa_t l2_gpa"
In x86's nested TDP APIs, use the appropriate gpa_t typedef and rename
variables from nested_paddr to l2_gpa to match KVM x86's nomenclature.
No functional change intended.
Link: https://patch.msgid.link/20260420212004.3938325-19-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| ea8bc95f | 13-Apr-2026 |
Paolo Bonzini <pbonzini@redhat.com> |
Merge tag 'kvm-x86-nested-7.1' of https://github.com/kvm-x86/linux into HEAD
KVM nested SVM changes for 7.1 (with one common x86 fix)
- To minimize the probability of corrupting guest state, defer
Merge tag 'kvm-x86-nested-7.1' of https://github.com/kvm-x86/linux into HEAD
KVM nested SVM changes for 7.1 (with one common x86 fix)
- To minimize the probability of corrupting guest state, defer KVM's
non-architectural delivery of exception payloads (e.g. CR2 and DR6) until
consumption of the payload is imminent, and force delivery of the payload
in all paths where userspace saves relevant state.
- Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT to fix a
bug where L2's CR2 can get corrupted after a save/restore, e.g. if the VM
is migrated while L2 is faulting in memory.
- Fix a class of nSVM bugs where some fields written by the CPU are not
synchronized from vmcb02 to cached vmcb12 after VMRUN, and so are not
up-to-date when saved by KVM_GET_NESTED_STATE.
- Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE and
KVM_SET_{S}REGS could cause vmcb02 to be incorrectly initialized after
save+restore.
- Add a variety of missing nSVM consistency checks.
- Fix several bugs where KVM failed to correctly update VMCB fields on nested
#VMEXIT.
- Fix several bugs where KVM failed to correctly synthesize #UD or #GP for
SVM-related instructions.
- Add support for save+restore of virtualized LBRs (on SVM).
- Refactor various helpers and macros to improve clarity and (hopefully) make
the code easier to maintain.
- Aggressively sanitize fields when copying from vmcb12 to guard against
unintentionally allowing L1 to utilize yet-to-be-defined features.
- Fix several bugs where KVM botched rAX legality checks when emulating SVM
instructions. Note, KVM is still flawed in that KVM doesn't address size
prefix overrides for 64-bit guests; this should probably be documented as a
KVM erratum.
- Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails instead of
somewhat arbitrarily synthesizing #GP (i.e. don't bastardize AMD's already-
sketchy behavior of generating #GP if for "unsupported" addresses).
- Cache all used vmcb12 fields to further harden against TOCTOU bugs.
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| d2ea4ff1 | 10-Mar-2026 |
Sean Christopherson <seanjc@google.com> |
KVM: selftests: Verify SEV+ guests can read and write EFER, CR0, CR4, and CR8
Add "do no harm" testing of EFER, CR0, CR4, and CR8 for SEV+ guests to
verify that the guest can read and write the regi
KVM: selftests: Verify SEV+ guests can read and write EFER, CR0, CR4, and CR8
Add "do no harm" testing of EFER, CR0, CR4, and CR8 for SEV+ guests to
verify that the guest can read and write the registers, without hitting
e.g. a #VC on SEV-ES guests due to KVM incorrectly trying to intercept a
register.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260310211841.2552361-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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| 7e6eab9b | 03-Mar-2026 |
Yosry Ahmed <yosry@kernel.org> |
KVM: SVM: Rename vmcb->virt_ext to vmcb->misc_ctl2
'virt' is confusing in the VMCB because it is relative and ambiguous.
The 'virt_ext' field includes bits for LBR virtualization and
VMSAVE/VMLOAD v
KVM: SVM: Rename vmcb->virt_ext to vmcb->misc_ctl2
'virt' is confusing in the VMCB because it is relative and ambiguous.
The 'virt_ext' field includes bits for LBR virtualization and
VMSAVE/VMLOAD virtualization, so it's just another miscellaneous control
field. Name it as such.
While at it, move the definitions of the bits below those for
'misc_ctl' and rename them for consistency.
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
Link: https://patch.msgid.link/20260303003421.2185681-20-yosry@kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| 1aea80dd | 03-Mar-2026 |
Sean Christopherson <seanjc@google.com> |
KVM: SVM: Rename vmcb->nested_ctl to vmcb->misc_ctl
The 'nested_ctl' field is misnamed. Although the first bit is for nested
paging, the other defined bits are for SEV/SEV-ES. Other bits in the
same
KVM: SVM: Rename vmcb->nested_ctl to vmcb->misc_ctl
The 'nested_ctl' field is misnamed. Although the first bit is for nested
paging, the other defined bits are for SEV/SEV-ES. Other bits in the
same field according to the APM (but not defined by KVM) include "Guest
Mode Execution Trap", "Enable INVLPGB/TLBSYNC", and other control bits
unrelated to 'nested'.
There is nothing common among these bits, so just name the field
misc_ctl. Also rename the flags accordingly.
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
Link: https://patch.msgid.link/20260303003421.2185681-19-yosry@kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| 53b28692 | 12-Feb-2026 |
Zhiquan Li <zhiquan_li@163.com> |
KVM: selftests: Add a flag to identify AMD compatible test cases
Most of KVM x86 selftests for AMD are compatible with Hygon architecture
(but not all), add a flag "host_cpu_is_amd_compatible" to fi
KVM: selftests: Add a flag to identify AMD compatible test cases
Most of KVM x86 selftests for AMD are compatible with Hygon architecture
(but not all), add a flag "host_cpu_is_amd_compatible" to figure out
these cases.
Following test failures on Hygon platform can be fixed:
* Fix hypercall test: Hygon architecture also uses VMMCALL as guest
hypercall instruction.
* Following test failures due to access reserved memory address regions:
- access_tracking_perf_test
- demand_paging_test
- dirty_log_perf_test
- dirty_log_test
- kvm_page_table_test
- memslot_modification_stress_test
- pre_fault_memory_test
- x86/dirty_log_page_splitting_test
Hygon CSV also makes the "physical address space width reduction", the
reduced physical address bits are reported by bits 11:6 of
CPUID[0x8000001f].EBX as well, so the existed logic is totally
applicable for Hygon processors. Mapping memory into these regions and
accessing to them results in a #PF.
Signed-off-by: Zhiquan Li <zhiquan_li@163.com>
Link: https://patch.msgid.link/20260212103841.171459-3-zhiquan_li@163.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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| 1b13885e | 09-Feb-2026 |
Paolo Bonzini <pbonzini@redhat.com> |
Merge tag 'kvm-x86-apic-6.20' of https://github.com/kvm-x86/linux into HEAD
KVM x86 APIC-ish changes for 6.20
- Fix a benign bug where KVM could use the wrong memslots (ignored SMM) when
creati
Merge tag 'kvm-x86-apic-6.20' of https://github.com/kvm-x86/linux into HEAD
KVM x86 APIC-ish changes for 6.20
- Fix a benign bug where KVM could use the wrong memslots (ignored SMM) when
creating a vCPU-specific mapping of guest memory.
- Clean up KVM's handling of marking mapped vCPU pages dirty.
- Drop a pile of *ancient* sanity checks hidden behind in KVM's unused
ASSERT() macro, most of which could be trivially triggered by the guest
and/or user, and all of which were useless.
- Fold "struct dest_map" into its sole user, "struct rtc_status", to make it
more obvious what the weird parameter is used for, and to allow burying the
RTC shenanigans behind CONFIG_KVM_IOAPIC=y.
- Bury all of ioapic.h and KVM_IRQCHIP_KERNEL behind CONFIG_KVM_IOAPIC=y.
- Add a regression test for recent APICv update fixes.
- Rework KVM's handling of VMCS updates while L2 is active to temporarily
switch to vmcs01 instead of deferring the update until the next nested
VM-Exit. The deferred updates approach directly contributed to several
bugs, was proving to be a maintenance burden due to the difficulty in
auditing the correctness of deferred updates, and was polluting
"struct nested_vmx" with a growing pile of booleans.
- Handle "hardware APIC ISR", a.k.a. SVI, updates in kvm_apic_update_apicv()
to consolidate the updates, and to co-locate SVI updates with the updates
for KVM's own cache of ISR information.
- Drop a dead function declaration.
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