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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 06 Jun 2012 22:25:57 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Ben Hutchings <bhutchings@...arflare.com>
Cc:	"Michael S. Tsirkin" <mst@...hat.com>,
	Stephen Hemminger <shemminger@...tta.com>,
	Jason Wang <jasowang@...hat.com>, netdev@...r.kernel.org,
	rusty@...tcorp.com.au, linux-kernel@...r.kernel.org,
	virtualization@...ts.linux-foundation.org
Subject: Re: [PATCH] virtio-net: fix a race on 32bit arches

On Wed, 2012-06-06 at 21:19 +0100, Ben Hutchings wrote:
> On Wed, 2012-06-06 at 22:08 +0200, Eric Dumazet wrote:
> > 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.
> 
> You have the NAPI 'lock', so when gathering stats you can synchronise
> using napi_disable() ;-)

Nice, this adds one new bug in network stack.

Really guys, can we stop this thread, please ?



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/