From owner-freebsd-current@FreeBSD.ORG Sun Apr 5 09:05:26 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EE8B61065676 for ; Sun, 5 Apr 2009 09:05:26 +0000 (UTC) (envelope-from stb@lassitu.de) Received: from koef.zs64.net (koef.zs64.net [212.12.50.230]) by mx1.freebsd.org (Postfix) with ESMTP id 8561F8FC52 for ; Sun, 5 Apr 2009 09:05:26 +0000 (UTC) (envelope-from stb@lassitu.de) Received: from localhost by koef.zs64.net (8.14.3/8.14.3) with ESMTP id n3595Oc5004521 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Sun, 5 Apr 2009 11:05:24 +0200 (CEST) (envelope-from stb@lassitu.de) (authenticated as stb) Message-Id: <190B8595-BAF8-41F5-B63F-64604672BFD3@lassitu.de> From: Stefan Bethke To: Mark Powell In-Reply-To: <20090404124909.C24261@rust.salford.ac.uk> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v930.3) Date: Sun, 5 Apr 2009 11:05:23 +0200 References: <20090404124909.C24261@rust.salford.ac.uk> X-Mailer: Apple Mail (2.930.3) Cc: freebsd-current@freebsd.org Subject: Re: panic: vput: negative ref cnt X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 05 Apr 2009 09:05:27 -0000 Am 04.04.2009 um 13:55 schrieb Mark Powell: > Hi, > Getting a reproducable panic during backups: > > panic: vput: negative ref cnt > cpuid = 0 > KDB: enter: panic > [thread pid 3521 tid 100374 ] > Stopped at kdb_enter+0x3d: movq $0,0x654104(%rip) > db> bt > Tracing pid 3521 tid 100374 0xffffff008c79e380 > kdb_enter() at kdb_enter+0x3d > panic() at panic+0x176 > vput() at vput+0x10c > dounmount() at dounmount0x421 > unmount() at unmount+0x24b > syscall() at syscall+0x1bf > Xfast_syscall() at Xfast_syscall+0xab > --- syscall (22, FreeBSD ELF64, unmount), rip = 0x800695d7c, rsp = > 0x7fffffffe218, rbp = 0 --- > > My script takes a zfs snapshot, mounts the snapshot, backs it up > using star, then umounts the snapshot. The panic seems to occur on > the umount. This is a different panic from the one I was getting, but appears to occur under the same circumstances. I managed to avoid the panic by keeping the snapshot until the next run of my backup script, and not unmounting anything. See Stefan -- Stefan Bethke Fon +49 151 14070811