From mboxrd@z Thu Jan  1 00:00:00 1970
From: Colin Walters <walters@verbum.org>
Subject: Re: [GIT] Networking
Date: Thu, 20 Jan 2011 17:38:05 -0500
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Cc: Eric Dumazet <eric.dumazet@gmail.com>,
	David Miller <davem@davemloft.net>, akpm@linux-foundation.org,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
To: Linus Torvalds <torvalds@linux-foundation.org>
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On Thu, Jan 20, 2011 at 5:21 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Thu, Jan 20, 2011 at 1:40 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>>
>> Then here ask for fd=3 both POLLIN and POLLOUT :
>> kernel answers : OK for POLLOUT (not POLLIN), so previous poll() call
>> was OK to be blocked after all...
>>
>> So I'm wondering if it could be a userland bug, that triggers with
>> recent kernel changes.
>
> As far as I can tell, that program isn't multi-threaded

It is actually; see src/gs-auth-pam.c; there is some pretty scary code
there; basically all of PAM is put in a thread to avoid blocking the
mainloop.  Whether the code is actually buggy I can't say immediately;
it's certainly possible.