From owner-freebsd-current Tue Jun 26 21:46: 2 2001 Delivered-To: freebsd-current@freebsd.org Received: from server.baldwin.cx (server.baldwin.cx [204.216.28.80]) by hub.freebsd.org (Postfix) with ESMTP id 04B1037B406 for ; Tue, 26 Jun 2001 21:45:54 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Received: from laptop.baldwin.cx (tserver.conference.usenix.org [199.103.159.3]) by server.baldwin.cx (8.9.3/8.9.3) with ESMTP id VAA20459; Tue, 26 Jun 2001 21:47:15 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <20010627101230R.matusita@jp.FreeBSD.org> Date: Tue, 26 Jun 2001 21:45:44 -0700 (PDT) From: John Baldwin To: Makoto MATSUSHITA Subject: Re: lock order reversal Cc: current@freebsd.org Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On 27-Jun-01 Makoto MATSUSHITA wrote: > > matusita> lock order reversal > matusita> 1st 0xc5d2043c process lock @ ../../vm/vm_glue.c:487 > matusita> 2nd 0xc05a9ec0 lockmgr interlock @ ../../kern/kern_lock.c:239 > > I've caught tracelog of this reversal, with debug.witness_ddb=1. > Here's console log: > > lock order reversal > 1st 0xc5e3cfdc process lock @ ../../vm/vm_glue.c:487 > 2nd 0xc05a9f80 lockmgr interlock @ ../../kern/kern_lock.c:239 > Debugger("witness_lock") > Stopped at Debugger+0x44: pushl %ebx > db> trace > Debugger(c02bd5ae) at Debugger+0x44 > witness_lock(c05a9f80,8,c02b8d54,ef) at witness_lock+0x90d > lockmgr(c5dbe7d0,12,0,c5420640) at lockmgr+0x97 > swapout_procs(1,c02686e0,c5420640,0,c582df94) at swapout_procs+0xc46 > vm_daemon(0,c582dfa8) at vm_daemon+0x128 > fork_exit(c02686e0,0,c582dfa8) at fork_exit+0xb4 > fork_trampoline() at fork_trampoline+0x8 > db> > > I don't know whether it is reproducible, but it's early morning (6 AM), > mkisofs(1) is just running to make an ISO image for me (for backup). Ok, this one is due to braindeadedness in lockmgr(), and will just have to stay the way it is until vm map locks switch to being sx locks instead of lockmgr locks. -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message