Re: [PATCH] virtio-net: fix a race on 32bit arches

From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Sun, 10 Jun 2012 13:25:12 +0300

On Wed, Jun 06, 2012 at 10:35:24AM +0200, Eric Dumazet wrote:

quoted

From: Eric Dumazet <edumazet@google.com>

commit 3fa2a1df909 (virtio-net: per cpu 64 bit stats (v2)) added a race
on 32bit arches.

We must use separate syncp for rx and tx path as they can be run at the
same time on different cpus. Thus one sequence increment can be lost and
readers spin forever.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Hemminger <redacted>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <redacted>

I'm still thinking about moving tx to take a xmit lock long term,
meanwhile this fix appears appropriate for 3.5.

Acked-by: Michael S. Tsirkin <mst@redhat.com>

Dave, can you pick this up pls?

Done, thanks.