[PATCH 1/8] KVM: SVM: Fix nested nmi handling

Joerg Roedel
2010-04-22T10:33:32Z

The patch introducing nested nmi handling had a bug. The
check does not belong to enable_nmi_window but must be in
nmi_allowed. This patch fixes this.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/kvm/svm.c | 16 +++++++++-------
1 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index ab78eb8..ec20584 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2771,8 +2771,12 @@ static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
struct vmcb *vmcb = svm->vmcb;
- return !(vmcb->control.int_state & SVM_INTERRUPT_SHADOW_MASK) &&
- !(svm->vcpu.arch.hflags & HF_NMI_MASK);
+ int ret;
+ ret = !(vmcb->control.int_state & SVM_INTERRUPT_SHADOW_MASK) &&
+ !(svm->vcpu.arch.hflags & HF_NMI_MASK);
+ ret = ret && gif_set(svm) && nested_svm_nmi(svm);
+
+ return ret;
}

static bool svm_get_nmi_mask(struct kvm_vcpu *vcpu)
@@ -2841,11 +2845,9 @@ static void enable_nmi_window(struct kvm_vcpu *vcpu)
* Something prevents NMI from been injected. Single step over possible
* problem (IRET or exception injection or interrupt shadow)
*/
- if (gif_set(svm) && nested_svm_nmi(svm)) {
- svm->nmi_singlestep = true;
- svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF);
- update_db_intercept(vcpu);
- }
+ svm->nmi_singlestep = true;
+ svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF);
+ update_db_intercept(vcpu);
}

static int svm_set_tss_addr(struct kvm *kvm, unsigned int addr)
--
1.7.0.4