From owner-freebsd-current@FreeBSD.ORG Mon Oct 3 08:16:00 2005 Return-Path: X-Original-To: freebsd-current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id ABA7F16A41F for ; Mon, 3 Oct 2005 08:16:00 +0000 (GMT) (envelope-from rik@cronyx.ru) Received: from hanoi.cronyx.ru (hanoi.cronyx.ru [144.206.181.53]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0161F43D49 for ; Mon, 3 Oct 2005 08:15:59 +0000 (GMT) (envelope-from rik@cronyx.ru) Received: (from root@localhost) by hanoi.cronyx.ru (8.13.0/vak/3.0) id j938CvwY050646 for freebsd-current@FreeBSD.org.checked; Mon, 3 Oct 2005 12:12:57 +0400 (MSD) (envelope-from rik@cronyx.ru) Received: from [144.206.181.94] (hi.cronyx.ru [144.206.181.94]) by hanoi.cronyx.ru (8.13.0/vak/3.0) with ESMTP id j938AZnG050606; Mon, 3 Oct 2005 12:10:36 +0400 (MSD) (envelope-from rik@cronyx.ru) Message-ID: <4340E785.3030705@cronyx.ru> Date: Mon, 03 Oct 2005 12:10:45 +0400 From: Roman Kurakin User-Agent: Mozilla Thunderbird 0.9 (Windows/20041103) X-Accept-Language: en-us, en MIME-Version: 1.0 To: John Baldwin References: <200501181124.19323.jhb@FreeBSD.org> In-Reply-To: <200501181124.19323.jhb@FreeBSD.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Bjoern A. Zeeb" , freebsd-current@FreeBSD.org, FreeBSD current mailing list Subject: Re: LOR: kern_descrip.c:2277,2278 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: Mon, 03 Oct 2005 08:16:00 -0000 Hi, Could you check: http://lists.freebsd.org/pipermail/freebsd-current/2005-September/056078.html Best regards, rik John Baldwin wrote: >On Monday 17 January 2005 05:07 pm, Bjoern A. Zeeb wrote: > > >>Hi, >> >>I have added the following as LOR #055 to "the LOR page"[1]. >> >>lock order reversal >> 1st 0xffffffff80c3a9e8 sleep mtxpool (sleep mtxpool) @ >>sys/kern/kern_descrip.c:2277 2nd 0xffffff00222d8a48 filedesc structure >>(filedesc structure) @ sys/kern/kern_descrip.c:2278 KDB: stack backtrace: >>witness_checkorder() at witness_checkorder+0x5f1 >>_mtx_lock_flags() at _mtx_lock_flags+0x4a >>dupfdopen() at dupfdopen+0x320 >>kern_open() at kern_open+0x5de >>syscall() at syscall+0x4ab >>Xfast_syscall() at Xfast_syscall+0xa8 >>--- syscall (5, FreeBSD ELF64, open), rip = 0x80077e7d0, rsp = >>0x7fffffffe6f8, rbp = 0x7fffffffec70 --- >> >>I can easily reproduce it every boot. It seems to be triggered by >>Capi4BSD[2] framework which I incorporated in my private tree. >> >>Can someone please comment on this ? >> >> > >The problem is that FILEDESC_UNLOCK() actually includes an entirely separate >lock of its own (it's like an sx lock sort of). One possible fix might be to >change struct file to either use a dedicated mutex pool (instead of the more >generic mtxpool_sleep one that is intended only for leaf-lock usage) or to >have each struct file include its own mutex rather than using a pool lock. > >