From owner-freebsd-stable@FreeBSD.ORG Thu Sep 6 16:32:08 2012 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 360DF106566B; Thu, 6 Sep 2012 16:32:08 +0000 (UTC) (envelope-from h.schmalzbauer@omnilan.de) Received: from host.omnilan.net (s1.omnilan.net [62.245.232.135]) by mx1.freebsd.org (Postfix) with ESMTP id AF4FF8FC0C; Thu, 6 Sep 2012 16:32:07 +0000 (UTC) Received: from titan.inop.wdn.omnilan.net (titan.inop.wdn.omnilan.net [172.21.3.1]) (authenticated bits=0) by host.omnilan.net (8.13.8/8.13.8) with ESMTP id q86GWj3W067254 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 6 Sep 2012 18:32:45 +0200 (CEST) (envelope-from h.schmalzbauer@omnilan.de) Message-ID: <5048D006.8060007@omnilan.de> Date: Thu, 06 Sep 2012 18:32:06 +0200 From: Harald Schmalzbauer Organization: OmniLAN User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; de-DE; rv:1.9.2.8) Gecko/20100906 Lightning/1.0b2 Thunderbird/3.1.2 MIME-Version: 1.0 To: attilio@freebsd.org References: <5022840B.3060708@omnilan.de> <5048C6D1.8020007@omnilan.de> In-Reply-To: <5048C6D1.8020007@omnilan.de> X-Enigmail-Version: 1.1.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: stable@freebsd.org, daichi@freebsd.org, Pavel Polyakov Subject: Re: lock violation in unionfs (9.0-STABLE r230270) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Sep 2012 16:32:08 -0000 schrieb Harald Schmalzbauer am 06.09.2012 17:52 (localtime): > schrieb Attilio Rao am 09.08.2012 20:26 (localtime): >> On 8/8/12, Harald Schmalzbauer wrote: >>> schrieb Pavel Polyakov am 06.03.2012 11:20 (localtime): >>>>>> mount -t unionfs -o noatime /usr /mnt >>>>>> >>>>>> insmntque: mp-safe fs and non-locked vp: 0xfffffe01d96704f0 is not= >>>>>> exclusive locked but should be >>>>>> KDB: enter: lock violation >>>>> Pavel, >>>>> can you give a spin to this patch?: >>>>> http://www.freebsd.org/~attilio/unionfs_missing_insmntque_lock.patc= h >>>>> >>>>> I think that the unlocking is due at that point as the vnode lock c= an >>>>> be switch later on. >>>>> >>>>> Let me know what you think about it and what the test does. >>>> Thanks! >>>> This patch fixes the problem with lock violation. Sorry I've tested = it so >>>> late. >>> Hello, >>> >>> this patch still applies cleanly to RELENG_9_1. Was there another fix= >>> for the issue or has it just not been PR-sent and thus forgotten? >> Can you and Pavel try the attached patch? Unfortunately I had no time >> to test it, I just made in 5 free mins from a non-FreeBSD workstation,= > Sorry, couldn't test earlier, but now I did: > With this patch applied the machine hangs without debug kernel and the > latter gives the following panic: > System call nmount returning with the following locks held: > exclusive lockmgr ufs (ufs) r =3D 0 (0xc5438278) locked @ > src/sys/fs/unionfs/union_vnops.c:1938 > panic: witness_warn > cpuid =3D 0 > KDB: stack backtrace: > db_trace_self_wrapper(c0a04f7f,c0c112c4,d1de3bb4,c097aa8c,fc,...) at > db_trace_self_wrapper+0x26 > kdb_backtrace(c0a4965f,0,c09c2ede3c1c,0,...) at kdb_backtrace+0x2a > witness_warn(2,0,c0a4ac34,c0a0990a,286,...) at witness_warn+0x1e4 > syscall(d1de3d08) ar syscall+0x415 > Xint0x80_syscall() at Xint0x80_syscall+0x21 > --- syscall (0, FreeBSD ELF32, nosys), eip =3D 0x280b883f,esp =3D > 0xbfbfe46c, ebp =3D 0xbfbfede8 --- > KDB: enter: panic > [ thread pid 86 tid 100054 ] > Stopped ad kdb_enter+0x3a: movl $0,kdb_why > db> bt > Tracing pid 86 tid 100054 td 0xc541b000 > kdb_enter(c0a00d16,c0a09130,0,0,0,...) at panix+0x190 > witness_warn(2,0,x0a4ac34,c0a0990a,286,...) at witness_warn+0x1e4 > syscall(d1de3d08) at syscall+0x415 > Xint0x80_syscall() at Xint0x80_syscall+0x21 > > Hmm, I guess I forgot to install kernel debug symbols... > Coming back if I have more Don't see more with kernel-symbols installed... Have no clue about KDB...= One thing to mention: If I apply the subject's patch (http://www.freebsd.org/~attilio/unionfs_missing_insmntque_lock.patch) the machine doesn't panic. Please tell me if I can provide more info! -Harry