From owner-freebsd-current@FreeBSD.ORG Fri Sep 24 20:32:58 2004 Return-Path: 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 3625916A4CE for ; Fri, 24 Sep 2004 20:32:58 +0000 (GMT) Received: from mail5.speakeasy.net (mail5.speakeasy.net [216.254.0.205]) by mx1.FreeBSD.org (Postfix) with ESMTP id 066F343D46 for ; Fri, 24 Sep 2004 20:32:58 +0000 (GMT) (envelope-from jhb@FreeBSD.org) Received: (qmail 24231 invoked from network); 24 Sep 2004 20:32:57 -0000 Received: from dsl027-160-063.atl1.dsl.speakeasy.net (HELO server.baldwin.cx) ([216.27.160.63]) (envelope-sender ) encrypted SMTP for ; 24 Sep 2004 20:32:57 -0000 Received: from [10.50.40.210] (gw1.twc.weather.com [216.133.140.1]) (authenticated bits=0) by server.baldwin.cx (8.12.11/8.12.11) with ESMTP id i8OKWr9w020377; Fri, 24 Sep 2004 16:32:53 -0400 (EDT) (envelope-from jhb@FreeBSD.org) From: John Baldwin To: Pavel Gubin Date: Fri, 24 Sep 2004 16:30:38 -0400 User-Agent: KMail/1.6.2 References: <20040922095257.GA81709@ie.tusur.ru> <200409231029.47945.jhb@FreeBSD.org> <20040924201256.GB67823@ie.tusur.ru> In-Reply-To: <20040924201256.GB67823@ie.tusur.ru> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200409241630.38058.jhb@FreeBSD.org> X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on server.baldwin.cx cc: freebsd-current@FreeBSD.org Subject: Re: "xlock already held" panics on 5.3-BETA(3,4,5) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 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: Fri, 24 Sep 2004 20:32:58 -0000 On Friday 24 September 2004 04:12 pm, Pavel Gubin wrote: > On Thu, Sep 23, 2004 at 10:29:47AM -0400, John Baldwin wrote: > > > > > panic: _sx_xlock (user map): xlock already held @ > > > > > /var/data/5/src/sys/vm/vm_map.c:2997 cpuid = 0 > > > > > KDB: stack backtrace: > > > > > kdb_backtrace(100,c0f794e0,c0e983c8,1,bb5) at kdb_backtrace+0x29 > > > > > panic(c05eaffa,c05d320c,c05fd313,c05fd393,bb5) at panic+0x114 > > > > > _sx_xlock(c0e983c8,c05fd393,bb5) at _sx_xlock+0x44 > > > > > _vm_map_lock_read(c0e98384,c05fd393,bb5,1f49a0c,c113692c) at > > > > > _vm_map_lock_read+0x37 > > > > > vm_map_lookup(c9f49a64,bfca2000,1,c9f49a68,c9f49a58) at > > > > > vm_map_lookup+0x28 vm_fault(c0e98384,bfca2000,1,0,c0f794e0) at > > > > > vm_fault+0x66 > > > > > trap_pfault(c9f49b2c,0,bfca253c) at trap_pfault+0xd2 > > > > > trap(18,10,10,c0e98444,c0c95c48) at trap+0x30d > > > > > calltrap() at calltrap+0x5 > > > > > --- trap 0xc, eip = 0xc05b541c, esp = 0xc9f49b6c, ebp = 0xc9f49b78 > > > > > --- pmap_enter_quick(c0e98444,2894f000,c0d7c2e8,0,0) at > > > > > pmap_enter_quick+0xc8 > > > > > > > > This is the real bug, can you do 'l *0xc05b541c' from kgdb? > > > > > > (kgdb) l *0xc05b541c > > > 0xc05b541c is in pmap_enter_quick > > > (/var/data/5/src/sys/i386/i386/pmap.c:2130). > > [] > > > > 2129 pte = vtopte(va); > > > 2130 if (*pte) { > > > 2131 if (mpte != NULL) { > > > 2132 pmap_unwire_pte_hold(pmap, mpte); > > > 2133 mpte = NULL; > > > 2134 } > > I've digged a bit... > Seems that `if (*pte)' causes a Page Fault. So, is it legal for page to > be non-resident here? Well, I think the pte pointer is NULL meaning perhaps that there is no pte for the virtual address 'va', but alc@ or peter@ should know more about that than I. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org