diff options
| author | Ivan Orlov <iorlov@amazon.com> | 2024-12-17 21:14:56 +0300 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2024-12-19 02:14:45 +0300 |
| commit | 7bd7ff99110a2f63f758b292ab762cad16b85656 (patch) | |
| tree | c7dd97e15cc92a9c5cc56071fc0d226418842395 | |
| parent | 47ef3ef843c0f6e8006094d707b4aac18ed87e53 (diff) | |
| download | linux-7bd7ff99110a2f63f758b292ab762cad16b85656.tar.xz | |
KVM: SVM: Handle event vectoring error in check_emulate_instruction()
Detect unhandleable vectoring in check_emulate_instruction() to prevent
infinite retry loops on SVM, and to eliminate the main differences in how
VM-Exits during event vectoring are handled on SVM versus VMX. E.g. if
the vCPU puts its IDT in emulated MMIO memory and generates an event,
without the check_emulate_instruction() change, SVM will re-inject the
event and resume the guest, and effectively put the vCPU into an infinite
loop.
Signed-off-by: Ivan Orlov <iorlov@amazon.com>
Link: https://lore.kernel.org/r/20241217181458.68690-6-iorlov@amazon.com
[sean: grab "svm" locally, massage changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 07911ddf1efe..8fc2f4a97495 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4789,9 +4789,15 @@ static void svm_enable_smi_window(struct kvm_vcpu *vcpu) static int svm_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, void *insn, int insn_len) { + struct vcpu_svm *svm = to_svm(vcpu); bool smep, smap, is_user; u64 error_code; + /* Check that emulation is possible during event vectoring */ + if ((svm->vmcb->control.exit_int_info & SVM_EXITINTINFO_TYPE_MASK) && + !kvm_can_emulate_event_vectoring(emul_type)) + return X86EMUL_UNHANDLEABLE_VECTORING; + /* Emulation is always possible when KVM has access to all guest state. */ if (!sev_guest(vcpu->kvm)) return X86EMUL_CONTINUE; @@ -4888,7 +4894,7 @@ static int svm_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, * In addition, don't apply the erratum workaround if the #NPF occurred * while translating guest page tables (see below). */ - error_code = to_svm(vcpu)->vmcb->control.exit_info_1; + error_code = svm->vmcb->control.exit_info_1; if (error_code & (PFERR_GUEST_PAGE_MASK | PFERR_FETCH_MASK)) goto resume_guest; |