KVM: x86: make vapics_in_nmi_mode atomic

commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream.

Writes were a bit racy, but hard to turn into a bug at the same time.
(Particularly because modern Linux doesn't use this feature anymore.)

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[Actually the next patch makes it much, much easier to trigger the race
 so I'm including this one for stable@ as well. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f4a555beef19..41b06fca39f7 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -591,7 +591,7 @@ struct kvm_arch {
         struct kvm_pic *vpic;
         struct kvm_ioapic *vioapic;
         struct kvm_pit *vpit;
-        int vapics_in_nmi_mode;
+        atomic_t vapics_in_nmi_mode;
         struct mutex apic_map_lock;
         struct kvm_apic_map *apic_map;