drivers: hv: switch to use mb() instead of smp_mb()

Even if guest were compiled without SMP support, it could not assume that host
wasn't. So switch to use mb() instead of smp_mb() to force memory barriers for
UP guest.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index bf421e0efa1e..4004e54ef05d 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -434,7 +434,7 @@ static void vmbus_on_msg_dpc(unsigned long data)
                  * will not deliver any more messages since there is
                  * no empty slot
                  */
-                smp_mb();
+                mb();
 
                 if (msg->header.message_flags.msg_pending) {
                         /*