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| author | Radim Krčmář <rkrcmar@redhat.com> | 2014-03-11 22:11:18 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-03-24 08:38:18 +0400 |
| commit | c516a4c127a90e5889b72f1ad1b9da4005bba65b (patch) | |
| tree | fa9d5ff0df79c1dbd17d41e0beb8e0010a4df89a | |
| parent | 0f8141267dce8a719b294b6fcade653eaae7aa54 (diff) | |
| download | linux-c516a4c127a90e5889b72f1ad1b9da4005bba65b.tar.xz | |
KVM: SVM: fix cr8 intercept window
commit 596f3142d2b7be307a1652d59e7b93adab918437 upstream.
We always disable cr8 intercept in its handler, but only re-enable it
if handling KVM_REQ_EVENT, so there can be a window where we do not
intercept cr8 writes, which allows an interrupt to disrupt a higher
priority task.
Fix this by disabling intercepts in the same function that re-enables
them when needed. This fixes BSOD in Windows 2008.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/x86/kvm/svm.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index a14a6eaf871d..765210d4d925 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2985,10 +2985,8 @@ static int cr8_write_interception(struct vcpu_svm *svm) u8 cr8_prev = kvm_get_cr8(&svm->vcpu); /* instruction emulation calls kvm_set_cr8() */ r = cr_interception(svm); - if (irqchip_in_kernel(svm->vcpu.kvm)) { - clr_cr_intercept(svm, INTERCEPT_CR8_WRITE); + if (irqchip_in_kernel(svm->vcpu.kvm)) return r; - } if (cr8_prev <= kvm_get_cr8(&svm->vcpu)) return r; kvm_run->exit_reason = KVM_EXIT_SET_TPR; @@ -3550,6 +3548,8 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr) if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK)) return; + clr_cr_intercept(svm, INTERCEPT_CR8_WRITE); + if (irr == -1) return; |