I was running following script (trying to reproduce an ext4 error reported in another thread) and the kernel dies with below error. The place where it crashes is :- 2746 static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, 2747 struct stripe_head_state *s, 2748 int disks) 2749 { ..... 2754 set_bit(STRIPE_HANDLE, &sh->state); 2755 2756 BUG_ON(s->failed > 2); <============== !!!! [ 9663.343974] md/raid:md11: Disk failure on loop3, disabling device.[ 9663.343976] md/raid:md11: Operation continuing on 4 devices.[ 9668.547289] ------------[ cut here ]------------[ 9668.547327] kernel BUG at drivers/md/raid5.c:2756![ 9668.547356] invalid opcode: 0000 [#1] SMP [ 9668.547388] Modules linked in: parport_pc ppdev snd_hda_codec_hdmi snd_hda_codec_conexant aesni_intel cryptd aes_i586 aes_generic nfsd exportfs btusb nfs bluetooth lockd fscache auth_rpcgss nfs_acl sunrpc binfmt_misc joydev snd_hda_intel snd_hda_codec fuse snd_hwdep thinkpad_acpi snd_pcm snd_seq_midi uvcvideo snd_rawmidi snd_seq_midi_event arc4 snd_seq videodev i915 iwlagn mxm_wmi drm_kms_helper drm snd_timer psmouse snd_seq_device serio_raw mac80211 snd tpm_tis tpm nvram tpm_bios intel_ips cfg80211 soundcore i2c_algo_bit snd_page_alloc video lp parport usbhid hid raid10 raid456 async_raid6_recov async_pq ahci libahci firewire_ohci firewire_core crc_itu_t sdhci_pci sdhci e1000e raid6_pq async_xor xor async_memcpy async_tx raid1 raid0 multipath linear[ 9668.547951] [ 9668.547964] Pid: 6067, comm: md11_raid6 Tainted: G W 3.1.0-rc3+ #0 LENOVO 2537GH6/2537GH6[ 9668.548021] EIP: 0060:[<f878d590>] EFLAGS: 00010202 CPU: 3[ 9668.548056] EIP is at handle_stripe+0x1e60/0x1e70 [raid456][ 9668.548087] EAX: 00000005 EBX: ea589e00 ECX: 00000000 EDX: 00000003[ 9668.548121] ESI: 00000006 EDI: df059590 EBP: ded39f00 ESP: ded39e30[ 9668.548155] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068[ 9668.548186] Process md11_raid6 (pid: 6067, ti=ded38000 task=e364b2c0 task.ti=ded38000)[ 9668.548228] Stack:[ 9668.548241] ded39e38 c10167e8 00000002 c107ce85 00000001 ded39e4c 00009258 00000000[ 9668.548303] df0595b8 ded39e60 ea589e00 fffffffc 00000007 ea589f28 ea589e00 df059590[ 9668.548364] 00000000 e36b1d50 ded39e7c 00000000 00000000 00000000 00000000 00000007[ 9668.548424] Call Trace:[ 9668.548447] [<c10167e8>] ? sched_clock+0x8/0x10[ 9668.548477] [<c107ce85>] ? sched_clock_cpu+0xe5/0x150[ 9668.548509] [<f8787f39>] ? __release_stripe+0x109/0x160 [raid456][ 9668.548545] [<f8787fce>] ? release_stripe+0x3e/0x50 [raid456][ 9668.548580] [<f878f47a>] raid5d+0x3aa/0x510 [raid456][ 9668.548611] [<c107698d>] ? finish_wait+0x4d/0x70[ 9668.548641] [<c13fc3fd>] md_thread+0xed/0x120[ 9668.548669] [<c1076890>] ? add_wait_queue+0x50/0x50[ 9668.548697] [<c13fc310>] ? md_rdev_init+0x120/0x120[ 9668.548725] [<c107608d>] kthread+0x6d/0x80[ 9668.548750] [<c1076020>] ? flush_kthread_worker+0x80/0x80[ 9668.548784] [<c15419be>] kernel_thread_helper+0x6/0x10[ 9668.548814] Code: 44 01 40 f0 80 88 80 00 00 00 02 f0 80 88 80 00 00 00 20 8b 45 98 e9 7a f3 ff ff 0f 0b c7 40 38 03 00 00 00 b8 03 00 00 00 eb b4 <0f> 0b 0f 0b 0f 0b 0f 0b [ 9668.549063] md: md11: resync done.[ 9668.549087] 90 8d b4 26 00 00 00 00 55 89 e5 57 56 [ 9668.549159] EIP: [<f878d590>] handle_stripe+0x1e60/0x1e70 [raid456] SS:ESP 0068:ded39e30[ 9668.935138] ---[ end trace e71016c3ebaeb3bd ]--- The script to reproduce is : /home/mkatiyar> cat a.ksh #!/bin/ksh SUDO=sudo cmd() { sudo $* } device=/dev/md11 cd cmd mdadm --stop $device cmd mdadm --remove $device cmd umount /tmp/b for i in `seq 1 7` do cmd losetup -d /dev/loop$i done mkdir -p /tmp/a mkdir -p /tmp/b cd /tmp/a for i in `seq 1 7` do cmd rm /tmp/a/raid-$i cmd dd if=/dev/zero of=/tmp/a/raid-$i bs=4k count=25000 cmd losetup /dev/loop$i /tmp/a/raid-$i done cmd mdadm --create $device --level=6 --raid-devices=7 /dev/loop[1-7] cmd cat /proc/mdstat cmd mkfs.ext4 -b 4096 -i 4096 -m 0 $device cmd mount $device /tmp/b cmd mdadm --manage $device --fail /dev/loop1 cmd mdadm --manage $device --fail /dev/loop2 cmd dmesg -c > /dev/null 2>&1 cmd dd if=/dev/zero of=/tmp/b/testfile bs=1k count=1000 & cmd mdadm --manage $device --fail /dev/loop3 PS : I'm not part of the list, so please keep me in cc in the response. -- Thanks - Manish -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html