Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757470Ab2EJQEt (ORCPT ); Thu, 10 May 2012 12:04:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54096 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755344Ab2EJQEr (ORCPT ); Thu, 10 May 2012 12:04:47 -0400 Date: Thu, 10 May 2012 12:04:37 -0400 From: Dave Jones To: Linux Kernel Cc: linus-nfs@vger.kernel.org, bfields@fieldses.org, Fedora Kernel Team Subject: nfs triggering Root dentry has weird name <> Message-ID: <20120510160437.GA11707@redhat.com> Mail-Followup-To: Dave Jones , Linux Kernel , linus-nfs@vger.kernel.org, bfields@fieldses.org, Fedora Kernel Team MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3319 Lines: 53 We've been getting reports of this message for a while in Fedora (Since circa 3.1). There are two different flavours. One from readlink.. :WARNING: at fs/dcache.c:2460 prepend_path+0x11b/0x131() :Hardware name: System Product Name :Root dentry has weird name <> :Modules linked in: ppdev parport_pc lp parport fuse nfs fscache auth_rpcgss nfs_acl via drm lockd ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack_netbios_ns nf_conntrack_broadcast ip6table_filter nf_conntrack_tftp ip6_tables nf_conntrack snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device joydev snd_pcm via_rhine snd_timer snd mii soundcore snd_page_alloc shpchp asus_atk0110 i2c_viapro i2c_core microcode sunrpc xfs pata_acpi ata_generic pata_via sata_via [last unloaded: scsi_wait_scan] :Pid: 6635, comm: abrt-hook-ccpp Not tainted 3.1.0-7.fc16.x86_64 #1 :Call Trace: : [] warn_slowpath_common+0x83/0x9b : [] warn_slowpath_fmt+0x46/0x48 : [] prepend_path+0x11b/0x131 : [] path_with_deleted+0x70/0x79 : [] d_path+0xa1/0xc6 : [] proc_pid_readlink+0x71/0xcf : [] sys_readlinkat+0x73/0x95 : [] sys_readlink+0x1b/0x1d : [] system_call_fastpath+0x16/0x1b and one from getcwd... WARNING: at fs/dcache.c:2458 prepend_path+0x18c/0x1a0() Hardware name: P5KC Root dentry has weird name <> Modules linked in: vfat fat snd_usb_audio snd_usbmidi_lib snd_rawmidi nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack tcp_lp binfmt_misc ppdev parport_pc lp parport fcoe libfcoe libfc scsi_transport_fc scsi_tgt 8021q garp stp llc nfs lockd auth_rpcgss nfs_acl des_generic md4 nls_utf8 cifs fscache ip6t_REJECT fuse snd_hda_codec_hdmi microcode iTCO_wdt iTCO_vendor_support serio_raw snd_hda_codec_realtek i2c_i801 snd_hda_intel snd_hda_codec snd_hwdep asus_atk0110 snd_seq snd_seq_device snd_pcm atl1 mii snd_timer snd soundcore snd_page_alloc uinput sunrpc firewire_ohci firewire_core pata_acpi ata_generic usb_storage crc_itu_t pata_jmicron radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core [last unloaded: nf_conntrack] Pid: 18100, comm: view Tainted: G W 3.1.9-1.fc16.x86_64 #1 Call Trace: [] warn_slowpath_common+0x7f/0xc0 [] warn_slowpath_fmt+0x46/0x50 [] prepend_path+0x18c/0x1a0 [] sys_getcwd+0xf7/0x1e0 [] system_call_fastpath+0x16/0x1b The common thing seems to be NFS. I added a patch to print out vfsmnt->mnt_sb->s_type->name, and sure enough every report since has shown nfs in there. Despite how commonly we've had it reported, it seems to be very hard to reproduce. I managed to hit it once myself, but haven't seen it in a month or so since. Original reports at: https://bugzilla.redhat.com/show_bug.cgi?id=766277 https://bugzilla.redhat.com/show_bug.cgi?id=787171 Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/