From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] virtio-net: fix a race on 32bit arches
Date: Wed, 06 Jun 2012 22:08:09 +0200
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	Stephen Hemminger <shemminger@vyatta.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Wed, 2012-06-06 at 22:58 +0300, Michael S. Tsirkin wrote:

> Absolutely, I am talking about virtio here.  I'm not kicking
> u64_stats_sync idea I am just saying that simple locking
> would work for virtio and might be better as it
> gives us a way to get counters atomically.

Which lock do you own in the RX path ?

You'll have to add a lock in fast path. This sounds really a bad choice
to me.