From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Chmielewski Subject: sysfs Kernel BUG when RAID bitmap file has IO errors Date: Wed, 12 Mar 2008 10:40:18 +0100 Message-ID: <47D7A502.6020701@wpkg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: Linux-Raid , LKML List-Id: linux-raid.ids I have a RAID-5 bitmap file on external media: # cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sdb1[0] sdf1[4] sde1[3] sdd1[2] sdc1[1] 1562834944 blocks level 5, 64k chunk, algorithm 2 [5/5] [UUUUU] bitmap: 0/373 pages [0KB], 512KB chunk, file: /root/raid/bitmap unused devices: Unfortunately, that external media is flash which slowly dies: # md5sum /root/raid/bitmap md5sum: /root/raid/bitmap: Input/output error Let's access "/sys/block/md0/md/dev-sdd1/super": # cat /sys/block/md0/md/dev-sdd1/super # dmesg -c ------------[ cut here ]------------ Kernel BUG at 78178626 [verbose debug info unavailable] invalid opcode: 0000 [#8] Modules linked in: iscsi_scst crc32c libcrc32c scst_vdisk scst iptable_filter ip_tables x_tables as_iosched deadline_iosched nfs nfsd lockd nfs_acl auth_rpcgss sunrpc exportfs dm_snapshot dm_mirror bonding e1000 sata_mv Pid: 4901, comm: cat Tainted: G D (2.6.24.2-1 #1) EIP: 0060:[<78178626>] EFLAGS: 00010212 CPU: 0 EIP is at sysfs_read_file+0x88/0xd4 EAX: 00000001 EBX: 91611780 ECX: 00000000 EDX: 976fecc0 ESI: 00001000 EDI: 976fed20 EBP: 9745b344 ESP: 8353df54 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 Process cat (pid: 4901, ti=8353c000 task=7d4caa40 task.ti=8353c000) Stack: 93511080 0804b4d8 00001000 0804e000 91611794 783515f0 847e3380 0804e000 7817859e 00001000 7814ad7c 8353dfa0 00001000 847e3380 fffffff7 0804e000 8353c000 7814b0aa 8353dfa0 00000000 00000000 00000000 00000003 0804e000 Call Trace: [<7817859e>] sysfs_read_file+0x0/0xd4 [<7814ad7c>] vfs_read+0x88/0x10a [<7814b0aa>] sys_read+0x41/0x67 [<78103bca>] syscall_call+0x7/0xb ======================= Code: c0 74 61 8b 47 18 8b 4b 0c 8b 40 04 89 43 24 89 e8 8b 74 24 14 8b 57 14 ff 16 89 c6 89 f8 e8 18 0b 00 00 81 fe ff 0f 00 00 7e 04 <0f> 0b eb fe 85 f6 78 31 c7 43 20 00 00 00 00 89 33 eb 07 be f4 EIP: [<78178626>] sysfs_read_file+0x88/0xd4 SS:ESP 0068:8353df54 ---[ end trace 7e6d8636f39e737a ]--- -- Tomasz Chmielewski http://wpkg.org