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| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2021-09-07 19:35:30 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-09-22 17:33:15 +0300 |
| commit | 8d68bad6d869fae8f4d50ab6423538dec7da72d1 (patch) | |
| tree | cbb4a83c8f6c028192481b4f86d1ef9365280867 /arch/x86/kvm/vmx | |
| parent | 0bbc2ca8515f9cdf11df84ccb63dc7c44bc3d8f4 (diff) | |
| download | linux-8d68bad6d869fae8f4d50ab6423538dec7da72d1.tar.xz | |
KVM: nVMX: Filter out all unsupported controls when eVMCS was activated
Windows Server 2022 with Hyper-V role enabled failed to boot on KVM when
enlightened VMCS is advertised. Debugging revealed there are two exposed
secondary controls it is not happy with: SECONDARY_EXEC_ENABLE_VMFUNC and
SECONDARY_EXEC_SHADOW_VMCS. These controls are known to be unsupported,
as there are no corresponding fields in eVMCSv1 (see the comment above
EVMCS1_UNSUPPORTED_2NDEXEC definition).
Previously, commit 31de3d2500e4 ("x86/kvm/hyper-v: move VMX controls
sanitization out of nested_enable_evmcs()") introduced the required
filtering mechanism for VMX MSRs but for some reason put only known
to be problematic (and not full EVMCS1_UNSUPPORTED_* lists) controls
there.
Note, Windows Server 2022 seems to have gained some sanity check for VMX
MSRs: it doesn't even try to launch a guest when there's something it
doesn't like, nested_evmcs_check_controls() mechanism can't catch the
problem.
Let's be bold this time and instead of playing whack-a-mole just filter out
all unsupported controls from VMX MSRs.
Fixes: 31de3d2500e4 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210907163530.110066-1-vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx')
| -rw-r--r-- | arch/x86/kvm/vmx/evmcs.c | 12 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 9 |
2 files changed, 14 insertions, 7 deletions
diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c index 0dab1b7b529f..ba6f99f584ac 100644 --- a/arch/x86/kvm/vmx/evmcs.c +++ b/arch/x86/kvm/vmx/evmcs.c @@ -353,14 +353,20 @@ void nested_evmcs_filter_control_msr(u32 msr_index, u64 *pdata) switch (msr_index) { case MSR_IA32_VMX_EXIT_CTLS: case MSR_IA32_VMX_TRUE_EXIT_CTLS: - ctl_high &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; + ctl_high &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL; break; case MSR_IA32_VMX_ENTRY_CTLS: case MSR_IA32_VMX_TRUE_ENTRY_CTLS: - ctl_high &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; + ctl_high &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL; break; case MSR_IA32_VMX_PROCBASED_CTLS2: - ctl_high &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES; + ctl_high &= ~EVMCS1_UNSUPPORTED_2NDEXEC; + break; + case MSR_IA32_VMX_PINBASED_CTLS: + ctl_high &= ~EVMCS1_UNSUPPORTED_PINCTRL; + break; + case MSR_IA32_VMX_VMFUNC: + ctl_low &= ~EVMCS1_UNSUPPORTED_VMFUNC; break; } diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0c2c0d5ae873..f7eb0ce0ddb5 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1837,10 +1837,11 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) &msr_info->data)) return 1; /* - * Enlightened VMCS v1 doesn't have certain fields, but buggy - * Hyper-V versions are still trying to use corresponding - * features when they are exposed. Filter out the essential - * minimum. + * Enlightened VMCS v1 doesn't have certain VMCS fields but + * instead of just ignoring the features, different Hyper-V + * versions are either trying to use them and fail or do some + * sanity checking and refuse to boot. Filter all unsupported + * features out. */ if (!msr_info->host_initiated && vmx->nested.enlightened_vmcs_enabled) |