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Date: Wed, 21 Nov 2012 10:26:31 +0400
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Jack Vogel <jfvogel@gmail.com>
Subject: Re: igb diver crashes in head@241037
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Cc: Karim Fodil-Lemelin <fodillemlinkarim@gmail.com>, jfv@FreeBSD.org,
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  Jack,

On Tue, Nov 20, 2012 at 09:19:54AM -0800, Jack Vogel wrote:
J> > I'd suggest the following code:
J> >
J> >                 if (m)
J> >                         drbr_enqueue(ifp, txr->br, m);
J> >                 err = igb_mq_start_locked(ifp, txr, NULL);
J> >
J> > Which eventually leads us to all invocations of igb_mq_start_locked()
J> > called
J> > with third argument as NULL. This allows us to simplify this function.
J> >
J> > Patch for review attached.
J> >
J> >
J> Yes Gleb, I already have code in my internal tree which simply removes an
J> mbuf
J> pointer form the start_locked call and ALWAYS does a dequeue, start
J> similarly
J> will always enqueue. I just have been busy with ixgbe for a bit and have
J> not gotten
J> it committed yet.

  Since ixgbe work is performance tuning and this patch closes a kernel crash,
I'd ask to preempt the ixgbe job with this patch. :)

  Or you can approve my patch and I will check it in.

-- 
Totus tuus, Glebius.