From owner-freebsd-current@FreeBSD.ORG  Wed Jun 19 12:31:35 2013
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by hub.freebsd.org (Postfix) with ESMTP id 1B1F2205;
 Wed, 19 Jun 2013 12:31:35 +0000 (UTC)
 (envelope-from glebius@FreeBSD.org)
Received: from cell.glebius.int.ru (glebius.int.ru [81.19.69.10])
 by mx1.freebsd.org (Postfix) with ESMTP id 9BB201DC9;
 Wed, 19 Jun 2013 12:31:34 +0000 (UTC)
Received: from cell.glebius.int.ru (localhost [127.0.0.1])
 by cell.glebius.int.ru (8.14.7/8.14.7) with ESMTP id r5JCVVQf002582;
 Wed, 19 Jun 2013 16:31:31 +0400 (MSK)
 (envelope-from glebius@FreeBSD.org)
Received: (from glebius@localhost)
 by cell.glebius.int.ru (8.14.7/8.14.7/Submit) id r5JCVVKi002581;
 Wed, 19 Jun 2013 16:31:31 +0400 (MSK)
 (envelope-from glebius@FreeBSD.org)
X-Authentication-Warning: cell.glebius.int.ru: glebius set sender to
 glebius@FreeBSD.org using -f
Date: Wed, 19 Jun 2013 16:31:31 +0400
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Andre Oppermann <andre@freebsd.org>
Subject: Re: Panic in tcp_input
Message-ID: <20130619123131.GC1214@glebius.int.ru>
References: <51C17A3B.2030809@freebsd.org> <E1UpEPp-0000iW-Lq@clue.co.za>
 <E1UpEmc-0000ls-7Q@clue.co.za> <51C1A1FE.8040300@freebsd.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=koi8-r
Content-Disposition: inline
In-Reply-To: <51C1A1FE.8040300@freebsd.org>
User-Agent: Mutt/1.5.21 (2010-09-15)
Cc: jeffr@FreeBSD.org, Ian FREISLICH <ianf@clue.co.za>, current@freebsd.org
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
 <freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/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: Wed, 19 Jun 2013 12:31:35 -0000

On Wed, Jun 19, 2013 at 02:20:14PM +0200, Andre Oppermann wrote:
A> On 19.06.2013 11:34, Ian FREISLICH wrote:
A> > Andre Oppermann wrote:
A> >> On 19.06.2013 11:10, Ian FREISLICH wrote:
A> >>> Hi
A> >>>
A> >>> I'm seeing this panic quite regularly now.  Most recent sighting on r251858.
A> >>
A> >> This panic message is not very informative and very hard to extract any
A> >> meaningful hints.  Do you have a core dump and matching debug kernel?
A> >
A> > I do.  If you can send me your public ssh key in private email, I
A> > can give you access to the server in question.
A> 
A> It bombs while accessing a per-cpu counter:
A> 
A> (kgdb) frame 11
A> #11 0xffffffff8054518e in tcp_input (m=<value optimized out>, off0=Cannot access
A> memory at address 0x14)
A> at counter.h:45
A> 45              __asm __volatile("addq\t%1,%%gs:(%0)"
A> 
A> This seems to be a fallout of the recent UMA changes and its interaction
A> with the per-cpu counter(9) system.
A> 
A> Adding in and handing over to Gleb and Jeff as they touched this area last.

Ian has reported this panic several days before Jeff's changes :(

-- 
Totus tuus, Glebius.