Try to unprotect and retry the instruction execution before checking for unhandleable vectoring. If there is a write to a shadowed page table when vectoring an event, KVM should be able to unprotect the gfn and retry the instruction execution without returning an error to userspace.
This ensures that the subsequent patches won't make KVM exit to userspace when handling an intercepted #PF during vectoring without checking whether unprotect & retry is possible.
Suggested-by: Sean Christopherson seanjc@google.com Signed-off-by: Ivan Orlov iorlov@amazon.com --- V1 -> V2: - This patch wasn't included in V1. V2 -> V3: - This patch wasn't included in V2.
arch/x86/kvm/x86.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 849a6fc364b3..26faacc99c4c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9107,6 +9107,10 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, if (r == X86EMUL_RETRY_INSTR || r == X86EMUL_PROPAGATE_FAULT) return 1;
+ if (kvm_unprotect_and_retry_on_failure(vcpu, cr2_or_gpa, + emulation_type)) + return 1; + if (r == X86EMUL_UNHANDLEABLE_VECTORING) { kvm_prepare_event_vectoring_exit(vcpu, cr2_or_gpa); return 0;