[PATCH 3/5] KVM: SVM: Defer nmi processing until switch to host state is complete

From: Avi Kivity
Date: Thu Nov 08 2007 - 05:36:34 EST


If we stgi() too soon, nmis can reach the processor even though interrupts
are disabled, catching it in a half-switched state. Delay the stgi() until
we're done switching.

Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx>
---
drivers/kvm/svm.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c
index 3910358..7376805 100644
--- a/drivers/kvm/svm.c
+++ b/drivers/kvm/svm.c
@@ -1585,10 +1585,6 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
#endif
: "cc", "memory" );

- local_irq_disable();
-
- stgi();
-
if ((svm->vmcb->save.dr7 & 0xff))
load_db_regs(svm->host_db_regs);

@@ -1605,6 +1601,10 @@ static void svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)

reload_tss(vcpu);

+ local_irq_disable();
+
+ stgi();
+
svm->next_rip = 0;
}

--
1.5.3

-
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