From owner-freebsd-current@FreeBSD.ORG  Mon Nov  1 19:38:17 2004
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 20D9316A4CF
	for <current@freebsd.org>; Mon,  1 Nov 2004 19:38:17 +0000 (GMT)
Received: from fledge.watson.org (fledge.watson.org [204.156.12.50])
	by mx1.FreeBSD.org (Postfix) with ESMTP id ABCC143D5A
	for <current@freebsd.org>; Mon,  1 Nov 2004 19:38:16 +0000 (GMT)
	(envelope-from robert@fledge.watson.org)
Received: from fledge.watson.org (localhost [127.0.0.1])
	by fledge.watson.org (8.13.1/8.13.1) with ESMTP id iA1JbGOZ088250;
	Mon, 1 Nov 2004 14:37:16 -0500 (EST)
	(envelope-from robert@fledge.watson.org)
Received: from localhost (robert@localhost)iA1JbGHn088247;
	Mon, 1 Nov 2004 19:37:16 GMT	(envelope-from robert@fledge.watson.org)
Date: Mon, 1 Nov 2004 19:37:16 +0000 (GMT)
From: Robert Watson <rwatson@freebsd.org>
X-Sender: robert@fledge.watson.org
To: Arjan de Vet <devet@devet.org>
In-Reply-To: <20041101164723.GA7375@adv.devet.org>
Message-ID: <Pine.NEB.3.96L.1041101193549.87725D-100000@fledge.watson.org>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
cc: current@freebsd.org
Subject: Re: if_sk patch to get more info from people with problems
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 01 Nov 2004 19:38:17 -0000


On Mon, 1 Nov 2004, Arjan de Vet wrote:

> In article <1099326109.23508.133.camel@leguin> you write:
> 
> >On Mon, 2004-11-01 at 05:54, User Valera wrote:
> 
> [...]
> 
> >debug.mpsafenet=0 has been my cure here as well for basically the same
> >symptoms.  I'll apply this patch and get info on what hardware I have
> >soon.
> 
> I filed a bug report for if_sk.c for possibly related symptoms: 
> 
>     http://www.freebsd.org/cgi/query-pr.cgi?pr=kern%2F73038 The
> IFF_NEEDSGIANT flag seems to solve the problem but I need to do much
> more testing with it this week (had to go back to 5.2.1 because 5.3
> hangs for me after 1-1.5 days; still need to debug that one as well :(). 

Note that it could well be a locking bug in if_sk, but that
debug.mpsafenet and IFF_NEEDSGIANT both substantially change the timing in
the driver, so these changes could just mask an existing bug in your
configuration (yet still leave it present in other's).  The if_de bug
recently, btw, turned out to be an existing (real) bug that was unmasked
due to timing changes from running with IFF_NEEDSGIANT, but was in fact
(we believe) present even with Giant over the stack...

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Principal Research Scientist, McAfee Research