From owner-freebsd-fs@FreeBSD.ORG Wed Jul 29 13:03:45 2009 Return-Path: Delivered-To: freebsd-fs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7EF71106564A; Wed, 29 Jul 2009 13:03:45 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 51F878FC17; Wed, 29 Jul 2009 13:03:43 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua [212.40.38.101]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id QAA02442; Wed, 29 Jul 2009 16:03:40 +0300 (EEST) (envelope-from avg@icyb.net.ua) Message-ID: <4A7048A9.4020507@icyb.net.ua> Date: Wed, 29 Jul 2009 16:03:37 +0300 From: Andriy Gapon User-Agent: Thunderbird 2.0.0.22 (X11/20090630) MIME-Version: 1.0 To: Thomas Backman References: <20090727072503.GA52309@jpru.ffm.jpru.de> <4A6E06E6.9030300@mail.zedat.fu-berlin.de> <4A6EC9E2.5070200@icyb.net.ua> <20090729084723.GD1586@garage.freebsd.pl> <4A7030B6.8010205@icyb.net.ua> <97D5950F-4E4D-4446-AC22-92679135868D@exscape.org> In-Reply-To: <97D5950F-4E4D-4446-AC22-92679135868D@exscape.org> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-fs@FreeBSD.org, FreeBSD current , Pawel Jakub Dawidek Subject: Re: zfs: Fatal trap 12: page fault while in kernel mode X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Jul 2009 13:03:46 -0000 on 29/07/2009 15:45 Thomas Backman said the following: > On Jul 29, 2009, at 13:21, Andriy Gapon wrote: > >> on 29/07/2009 13:32 Thomas Backman said the following: >>> OFF TOPIC: >>> Due to similarities in the backtrace between this and a panic I've been >>> seeing on exporting after zfs recv (see >>> http://lists.freebsd.org/pipermail/freebsd-current/2009-July/009105.html and >>> >>> also >>> http://lists.freebsd.org/pipermail/freebsd-current/2009-July/009174.html for >>> [snip] > The DDB output from one panic does involve zfs_znode_dmu_fini and > dmu_buf_update_user: > _sx_xlock() > dmu_buf_update_user()+0x47 > zfs_znode_dmu_fini() > zfs_freebsd_reclaim() > VOP_RECLAIM_APV() > vgonel() > vflush() > zfs_umount() > dounmount() > unmount() > syscall() > Xfast_syscall() > (Sorry if the formatting got screwed up above.) Hmm, then you experienced two different kinds of panics. To quote the link you posted earlier: [1] http://lists.freebsd.org/pipermail/freebsd-current/2009-July/009174.html ... #10 0xffffffff8086e007 in calltrap () at /usr/src/sys/amd64/amd64/exception.S:223 #11 0xffffffff805a4989 in _sx_xlock_hard (sx=0xffffff0043557d50, tid=18446742975830720512, opts=Variable "opts" is not available.) at /usr/src/sys/kern/kern_sx.c:575 #12 0xffffffff805a52fe in _sx_xlock (sx=Variable "sx" is not available.) at sx.h:155 #13 0xffffffff80fe2995 in zfs_freebsd_reclaim () from /boot/kernel/zfs.ko ... So now that you said that the patch didn't fix the problem for you, could you please clarify what panic you do see after applying it? >> BTW, have you tried to reproduce the problem with INVARIANTS enabled? >> Do you have crashdumps with debugging symbols? > > I tried again with INVARIANTS, but see no difference in the panic, the > DDB bt or the KGDB bt. What does invariants really do? (Not sure how to > use it to my advantage here :) INVARIANTS enables KASSERTs in various parts of code which can help to catch bugs earlier that may result in cryptic panics afterwards. > Re: debugging symbols; isn't that the default? I do have a .symbols file > for all the files in /boot/kernel, but that's all I know to be honest. Ok, then if you get a crash dump, you are able use kgdb and it will be able to produce line numbers and will allow to examine variables. P.S. sorry if I miss context of your previous reports. -- Andriy Gapon