diff options
| author | Sean Christopherson <seanjc@google.com> | 2024-04-17 07:30:29 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-05-07 11:59:18 -0400 |
| commit | dee281e4b4355286c76d1788dc8e65ec236d6e04 (patch) | |
| tree | 271587a963ee4d1e65d735a8b9496d2103212298 /arch/x86/kvm/svm | |
| parent | 9b62e03e192ce9300608f9be69be9854a166eae3 (diff) | |
KVM: x86: Move synthetic PFERR_* sanity checks to SVM's #NPF handler
Move the sanity check that hardware never sets bits that collide with KVM-
define synthetic bits from kvm_mmu_page_fault() to npf_interception(),
i.e. make the sanity check #NPF specific. The legacy #PF path already
WARNs if _any_ of bits 63:32 are set, and the error code that comes from
VMX's EPT Violatation and Misconfig is 100% synthesized (KVM morphs VMX's
EXIT_QUALIFICATION into error code flags).
Add a compile-time assert in the legacy #PF handler to make sure that KVM-
define flags are covered by its existing sanity check on the upper bits.
Opportunistically add a description of PFERR_IMPLICIT_ACCESS, since we
are removing the comment that defined it.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Message-ID: <20240228024147.41573-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 0f3b59da0d4a..535018f152a3 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2047,6 +2047,15 @@ static int npf_interception(struct kvm_vcpu *vcpu) u64 fault_address = svm->vmcb->control.exit_info_2; u64 error_code = svm->vmcb->control.exit_info_1; + /* + * WARN if hardware generates a fault with an error code that collides + * with KVM-defined sythentic flags. Clear the flags and continue on, + * i.e. don't terminate the VM, as KVM can't possibly be relying on a + * flag that KVM doesn't know about. + */ + if (WARN_ON_ONCE(error_code & PFERR_SYNTHETIC_MASK)) + error_code &= ~PFERR_SYNTHETIC_MASK; + trace_kvm_page_fault(vcpu, fault_address, error_code); return kvm_mmu_page_fault(vcpu, fault_address, error_code, static_cpu_has(X86_FEATURE_DECODEASSISTS) ? |