From 00682995409696866fe43984c74c8688bdf8f0a5 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 24 Aug 2023 18:36:21 -0700 Subject: KVM: SVM: Treat all "skip" emulation for SEV guests as outright failures Treat EMULTYPE_SKIP failures on SEV guests as unhandleable emulation instead of simply resuming the guest, and drop the hack-a-fix which effects that behavior for the INT3/INTO injection path. If KVM can't skip an instruction for which KVM has already done partial emulation, resuming the guest is undesirable as doing so may corrupt guest state. Link: https://lore.kernel.org/r/20230825013621.2845700-5-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/svm.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-) (limited to 'arch/x86/kvm/svm/svm.c') diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index c4e700f945f8..b7472ad183b9 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -364,8 +364,6 @@ static void svm_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask) svm->vmcb->control.int_state |= SVM_INTERRUPT_SHADOW_MASK; } -static int svm_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, - void *insn, int insn_len); static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, bool commit_side_effects) @@ -386,14 +384,6 @@ static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, } if (!svm->next_rip) { - /* - * FIXME: Drop this when kvm_emulate_instruction() does the - * right thing and treats "can't emulate" as outright failure - * for EMULTYPE_SKIP. - */ - if (svm_check_emulate_instruction(vcpu, EMULTYPE_SKIP, NULL, 0) != X86EMUL_CONTINUE) - return 0; - if (unlikely(!commit_side_effects)) old_rflags = svm->vmcb->save.rflags; @@ -4781,7 +4771,7 @@ static int svm_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, */ if (unlikely(!insn)) { if (emul_type & EMULTYPE_SKIP) - return X86EMUL_RETRY_INSTR; + return X86EMUL_UNHANDLEABLE; kvm_queue_exception(vcpu, UD_VECTOR); return X86EMUL_PROPAGATE_FAULT; -- cgit v1.2.3