From mboxrd@z Thu Jan  1 00:00:00 1970
From: Willy Tarreau <w@1wt.eu>
Subject: Re: [PATCH] tcp: splice: fix an infinite loop in tcp_read_sock()
Date: Fri, 11 Jan 2013 00:21:53 +0100
Message-ID: <20130110232153.GE17390@1wt.eu>
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Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, Jan 10, 2013 at 03:05:55PM -0800, Eric Dumazet wrote:
> On Fri, 2013-01-11 at 00:01 +0100, Willy Tarreau wrote:
> > Hi Eric,
> 
> > Thanks for catching this one. I'm amazed we didn't notice it earlier,
> > I've been running my stress-test kernels with this patch applied since
> > we did it.
> > 
> 
> Thats because you splice(    very_large_amount_of_bytes), so you dont
> hit this bug.

Not always, I use many sizes (from 1k to very large).

> netperf does the splice (    exact_amount_of_bytes ) so hits this pretty
> fast on loopback at least.

OK I see, if we need an exact size to trigger it, that explains it !

Thanks for the explanation,
Willy