3.2.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jason Wang <jasowang@xxxxxxxxxx> commit 35848f68b07df3f917cb13fc3c134718669f569b upstream. 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@xxxxxxxxxx> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> [bwh: Backported to 3.2: - Drop changes to functions that don't exist here - hv_ringbuffer_write() has only a write memory barrier] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -383,7 +383,7 @@ int hv_ringbuffer_write(struct hv_ring_b sizeof(u64)); /* Make sure we flush all writes before updating the writeIndex */ - smp_wmb(); + wmb(); /* Now, update the write location */ hv_set_next_write_location(outring_info, next_write_location); --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -466,7 +466,7 @@ static void vmbus_on_msg_dpc(unsigned lo * will not deliver any more messages since there is * no empty slot */ - smp_mb(); + mb(); if (msg->header.message_flags.msg_pending) { /* -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html