From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] [PATCH] Fix deadlock in af_packet while stressing raw
 ethernet socket interface
Date: Tue, 12 Jul 2011 10:23:06 +0200
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To: David Miller <davem@davemloft.net>
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Le mardi 12 juillet 2011 =C3=A0 00:19 -0700, David Miller a =C3=A9crit =
:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Tue, 12 Jul 2011 08:58:48 +0200
>=20
> > This seems a bug, but in softirq handling in your arch
>=20
> That's not the problem, it's the dev_queue_xmit_nit() code
> path that interrupt is interrupting.

Isnt it what I said ?

Unless I am mistaken, dev_queue_xmit_nit() is called from
dev_hard_start_xmit(), and from dev_queue_xmit(), therefore BH
are/should_be masked. Calling do_softirq() while BH are masked is the
bug.

Something must be messing the !in_interrupt() test done from irq_exit()