[PATCH] KVM: SVM: fix NMI window after iret

From: Radim KrÄmÃÅ
Date: Fri Jan 17 2014 - 14:54:10 EST

We should open NMI window right after an iret, but SVM exits before it.
We wanted to single step using the trap flag and then open it.
(or we could emulate the iret instead)
We don't do it since commit 3842d135ff2 (likely), because the iret exit
handler does not request an event, so NMI window remains closed until
the next exit.

Fix this by making KVM_REQ_EVENT request in the iret handler.

Signed-off-by: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
(btw. kvm-unit-tests weren't executed on SVM since Nov 2010, at least)

arch/x86/kvm/svm.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index c7168a5..b5a735b 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2829,6 +2829,7 @@ static int iret_interception(struct vcpu_svm *svm)
clr_intercept(svm, INTERCEPT_IRET);
svm->vcpu.arch.hflags |= HF_IRET_MASK;
svm->nmi_iret_rip = kvm_rip_read(&svm->vcpu);
+ kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
return 1;


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