KVM: Fix simultaneous NMIs
If simultaneous NMIs happen, we're supposed to queue the second
and next (collapsing them), but currently we sometimes collapse
the second into the first.
Fix by using a counter for pending NMIs instead of a bool; since
the counter limit depends on whether the processor is currently
in an NMI handler, which can only be checked in vcpu context
(via the NMI mask), we add a new KVM_REQ_NMI to request recalculation
of the counter.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 2a414f6..d526231 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -49,6 +49,7 @@
#define KVM_REQ_EVENT 11
#define KVM_REQ_APF_HALT 12
#define KVM_REQ_STEAL_UPDATE 13
+#define KVM_REQ_NMI 14
#define KVM_USERSPACE_IRQ_SOURCE_ID 0