The problem exists only on VMX. Also currently we skip this step if there is pending exception. The patch fixes this too. Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx> --- arch/x86/kvm/vmx.c | 8 ++++++++ arch/x86/kvm/x86.c | 3 --- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index fe2ce2b..ec378c1 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3388,6 +3388,14 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) if (test_bit(VCPU_REGS_RIP, (unsigned long *)&vcpu->arch.regs_dirty)) vmcs_writel(GUEST_RIP, vcpu->arch.regs[VCPU_REGS_RIP]); + /* When single-stepping over STI and MOV SS, we must clear the + * corresponding interruptibility bits in the guest state. Otherwise + * vmentry fails as it then expects bit 14 (BS) in pending debug + * exceptions being set, but that's not correct for the guest debugging + * case. */ + if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) + vmx_set_interrupt_shadow(vcpu, 0); + /* * Loading guest fpu may have cleared host cr0.ts */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a08d96f..82585ae 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3153,9 +3153,6 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu) static void inject_pending_irq(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { - if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) - kvm_x86_ops->set_interrupt_shadow(vcpu, 0); - /* try to reinject previous events if any */ if (vcpu->arch.nmi_injected) { kvm_x86_ops->set_nmi(vcpu); -- 1.6.2.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html