From owner-freebsd-stable@FreeBSD.ORG Fri Mar 21 08:15:51 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 3CDC6FE2 for ; Fri, 21 Mar 2014 08:15:51 +0000 (UTC) Received: from elf.hq.norma.perm.ru (mail.norma.perm.ru [IPv6:2001:470:1f09:14c0::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 8B73794F for ; Fri, 21 Mar 2014 08:15:50 +0000 (UTC) Received: from bsdrookie.norma.com. (bsdrookie.norma.com [192.168.7.224]) by elf.hq.norma.perm.ru (8.14.5/8.14.5) with ESMTP id s2L8FjkU091672 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO) for ; Fri, 21 Mar 2014 14:15:46 +0600 (YEKT) (envelope-from emz@norma.perm.ru) Message-ID: <532BF531.1050400@norma.perm.ru> Date: Fri, 21 Mar 2014 14:15:45 +0600 From: "Eugene M. Zheganin" User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: freebsd-stable Subject: Re: crash on zpool import - help get data back References: <532BEABC.5050808@norma.perm.ru> In-Reply-To: <532BEABC.5050808@norma.perm.ru> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (elf.hq.norma.perm.ru [192.168.3.10]); Fri, 21 Mar 2014 14:15:46 +0600 (YEKT) X-Spam-Status: No hits=-101.0 bayes=0.5 testhits ALL_TRUSTED=-1, USER_IN_WHITELIST=-100 autolearn=unavailable version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on elf.hq.norma.perm.ru X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Mar 2014 08:15:51 -0000 Hi. On 21.03.2014 13:31, Eugene M. Zheganin wrote: > Hi. > > After some time using zfs on a 10.x server (and a couple of panics) I'm > now getting the reproducible and repeatable panic on any operations > involving particular pool. I managed to boot from USB stick, import only > healthy pools and substitite the server's zpool.cache file with one > referencing only healthy pools. Now I'm able to boot, but when I try to > import the remaining pool I'm getting the panic (attached below). Now > questions: > > - do I understand correctly that "#7 0xffffffff8188e076 in > vdev_readable (vd=0x0)" means vd is NULL, and this is triggering the panic ? > - I saw a similar (but not identical) panic in > http://lists.freebsd.org/pipermail/freebsd-fs/2012-January/013513.html , > - are there any possible tricks that could help me getting my data ? After some thinking (speeded up with the superiors running in circles) I realized that the root cause is the same and I can apply the tricks mentioned above. However, the question remains - how could this happen, because the main difference between me and original thread author is that I don't have memory errors. Furthermore, may be this technique can be applied to the FreeBSD zfs code, for example switching affected vdevs into the DEGRADED state, like solaris fmadm does when it's getting errors on a disk, thus signalling that the pool actually isn't healthy anymore ? However, I am not a programmer of any kind, so this is just a thought based on a fact that two individuals independently stepped on same issue. Thanks. Eugene.