tree 88c703c5df493bc51a972c4051b51669b6bfb7a4
parent b689e86c9a8f81aa80f2ab8a4d5a4635f870af4b
author Ignacio Alvarado <ikalvarado@google.com> 1478286955 -0700
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1480150492 +0100

KVM: Disable irq while unregistering user notifier

commit 1650b4ebc99da4c137bfbfc531be4a2405f951dd upstream.

Function user_notifier_unregister should be called only once for each
registered user notifier.

Function kvm_arch_hardware_disable can be executed from an IPI context
which could cause a race condition with a VCPU returning to user mode
and attempting to unregister the notifier.

Signed-off-by: Ignacio Alvarado <ikalvarado@google.com>
Fixes: 18863bdd60f8 ("KVM: x86 shared msr infrastructure")
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>