From 1d5a4d9b92028d9fe77da34037bd5a1ebfecc733 Mon Sep 17 00:00:00 2001 From: Guillaume Thouvenin Date: Wed, 29 Oct 2008 09:39:42 +0100 Subject: KVM: VMX: Handle mmio emulation when guest state is invalid If emulate_invalid_guest_state is enabled, the emulator is called when guest state is invalid. Until now, we reported an mmio failure when emulate_instruction() returned EMULATE_DO_MMIO. This patch adds the case where emulate_instruction() failed and an MMIO emulation is needed. Signed-off-by: Guillaume Thouvenin Signed-off-by: Avi Kivity --- arch/x86/kvm/vmx.c | 27 +++++++++++++++------------ 1 file changed, 15 insertions(+), 12 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 816d23185fb8..427dbc14fae9 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3052,16 +3052,12 @@ static void handle_invalid_guest_state(struct kvm_vcpu *vcpu, while (!guest_state_valid(vcpu)) { err = emulate_instruction(vcpu, kvm_run, 0, 0, 0); - switch (err) { - case EMULATE_DONE: - break; - case EMULATE_DO_MMIO: - kvm_report_emulation_failure(vcpu, "mmio"); - /* TODO: Handle MMIO */ - return; - default: - kvm_report_emulation_failure(vcpu, "emulation failure"); - return; + if (err == EMULATE_DO_MMIO) + break; + + if (err != EMULATE_DONE) { + kvm_report_emulation_failure(vcpu, "emulation failure"); + return; } if (signal_pending(current)) @@ -3073,8 +3069,10 @@ static void handle_invalid_guest_state(struct kvm_vcpu *vcpu, local_irq_disable(); preempt_disable(); - /* Guest state should be valid now, no more emulation should be needed */ - vmx->emulation_required = 0; + /* Guest state should be valid now except if we need to + * emulate an MMIO */ + if (guest_state_valid(vcpu)) + vmx->emulation_required = 0; } /* @@ -3121,6 +3119,11 @@ static int kvm_handle_exit(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) KVMTRACE_3D(VMEXIT, vcpu, exit_reason, (u32)kvm_rip_read(vcpu), (u32)((u64)kvm_rip_read(vcpu) >> 32), entryexit); + /* If we need to emulate an MMIO from handle_invalid_guest_state + * we just return 0 */ + if (vmx->emulation_required && emulate_invalid_guest_state) + return 0; + /* Access CR3 don't cause VMExit in paging mode, so we need * to sync with guest real CR3. */ if (vm_need_ept() && is_paging(vcpu)) { -- cgit v1.2.2