From owner-freebsd-fs@FreeBSD.ORG Wed Dec 18 09:19:23 2013 Return-Path: Delivered-To: freebsd-fs@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 A0D1179C; Wed, 18 Dec 2013 09:19:23 +0000 (UTC) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id A681E18ED; Wed, 18 Dec 2013 09:19:22 +0000 (UTC) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id LAA08730; Wed, 18 Dec 2013 11:19:20 +0200 (EET) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1VtDHk-000LQk-7s; Wed, 18 Dec 2013 11:19:20 +0200 Message-ID: <52B16847.8090905@FreeBSD.org> Date: Wed, 18 Dec 2013 11:17:59 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: freebsd-fs Subject: namecache: numneg > 0 but ncneg is empty X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=X-VIET-VPS Content-Transfer-Encoding: 7bit Cc: Konstantin Belousov X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Dec 2013 09:19:23 -0000 I've been running a test that exercises vfs, fs and namecache code quite a lot and I have run into the following panic: #2 0xffffffff808e9b43 in panic (fmt=) at /usr/src/sys/kern/kern_shutdown.c:637 #3 0xffffffff80ce57dd in trap_fatal (frame=0xc, eva=18446744071578770679) at /usr/src/sys/amd64/amd64/trap.c:879 #4 0xffffffff80ce58a6 in trap_pfault (frame=0xffffff9de1875260, usermode=0) at /usr/src/sys/amd64/amd64/trap.c:700 #5 0xffffffff80ce60d7 in trap (frame=0xffffff9de1875260) at /usr/src/sys/amd64/amd64/trap.c:463 #6 0xffffffff80cce853 in calltrap () at /usr/src/sys/amd64/amd64/exception.S:232 #7 0xffffffff8097b46d in cache_zap (ncp=0x0) at /usr/src/sys/kern/vfs_cache.c:417 #8 0xffffffff8097c22f in cache_enter_time (dvp=0xfffffe031c7215f8, vp=0xfffffe0a684f05f8, cnp=0xffffff9de1875858, tsp=0x0, dtsp=0x0) at /usr/src/sys/kern/vfs_cache.c:902 #9 0xffffffff81b9b26c in zfs_lookup (dvp=0xfffffe031c7215f8, nm=0xffffff9de1875460 "5", vpp=0xffffff9de1875830, cnp=0xffffff9de1875858, nameiop=1, cr=0xfffffe0a8f937800, td=0xfffffe04a80c2490, flags=0) at /usr/src/sys/modules/zfs/../../cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c:1555 #10 0xffffffff81b9b338 in zfs_freebsd_lookup (ap=0xffffff9de18755d0) at /usr/src/sys/modules/zfs/../../cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c:5946 #11 0xffffffff80d8f403 in VOP_CACHEDLOOKUP_APV (vop=0xffffffff81c26ee0, a=0xffffff9de18755d0) at vnode_if.c:193 #12 0xffffffff8097cef3 in vfs_cache_lookup (ap=) at vnode_if.h:80 #13 0xffffffff80d8f623 in VOP_LOOKUP_APV (vop=0xffffffff81c26ee0, a=0xffffff9de18756b0) at vnode_if.c:126 #14 0xffffffff80984bed in lookup (ndp=0xffffff9de18757f0) at vnode_if.h:54 #15 0xffffffff80985a43 in namei (ndp=0xffffff9de18757f0) at /usr/src/sys/kern/vfs_lookup.c:294 #16 0xffffffff809981a2 in kern_mkdirat (td=0xfffffe04a80c2490, fd=-100, path=0x801c19110
, segflg=UIO_USERSPACE, mode=511) at /usr/src/sys/kern/vfs_syscalls.c:3830 #17 0xffffffff809983f6 in kern_mkdir (td=, path=, segflg=, mode=) at /usr/src/sys/kern/vfs_syscalls.c:3810 #18 0xffffffff80998414 in sys_mkdir (td=, uap=) at /usr/src/sys/kern/vfs_syscalls.c:3789 (kgdb) fr 8 #8 0xffffffff8097c22f in cache_enter_time (dvp=0xfffffe031c7215f8, vp=0xfffffe0a684f05f8, cnp=0xffffff9de1875858, tsp=0x0, dtsp=0x0) at /usr/src/sys/kern/vfs_cache.c:902 902 cache_zap(ncp); (kgdb) list 897 zap = 1; 898 } 899 if (hold) 900 vhold(dvp); 901 if (zap) 902 cache_zap(ncp); 903 CACHE_WUNLOCK(); 904 } 905 906 /* (kgdb) i loc ncp = (struct namecache *) 0x0 n2 = (struct namecache *) 0xffffffff8178a740 ncpp = (struct nchashhead *) 0xffffff8ccde4e9b0 hash = flag = 0 hold = 1 zap = 1 len = (kgdb) p numneg $4 = 437 (kgdb) p ncp $7 = (struct namecache *) 0x0 (kgdb) p ncneg $8 = {tqh_first = 0x0, tqh_last = 0xffffffff8178a710} I am not sure that there is a bug in namecache, but if there is one, then the only suspicious place I could find is ".." handling in cache_enter_time(). -- Andriy Gapon