On 31/12/15 19:10, Michael S. Tsirkin wrote: > drivers/xen/xenbus/xenbus_comms.c uses > full memory barriers to communicate with the other side. > > For guests compiled with CONFIG_SMP, smp_wmb and smp_mb > would be sufficient, so mb() and wmb() here are only needed if > a non-SMP guest runs on an SMP host. > > Switch to virt_xxx barriers which serve this exact purpose. Acked-by: David Vrabel <david.vrabel@xxxxxxxxxx> If you're feeling particularly keen there's a rmb() consume_one_event() in drivers/xen/events/events_fifo.c that can be converted to virt_rmb() as well. David
