For no apparent reason I cannot longer mount my RAID1-pair of 500GB-disks read/write. If I do this, the kernel crashes invariably a few seconds after the first read attempt. The syslog contains always: kernel: BTRFS critical (device sdc): unable to update root key 5 132 0 kernel: ------------[ cut here ]------------ kernel: kernel BUG at fs/btrfs/root-tree.c:160! kernel: invalid opcode: 0000 [#1] SMP Fortunately I can mount the disks read-only without problems. (So I will not try "btrfs check" before I have copied the disks.) "btrfs scrub" works and found no errors "btrfs rescue super-recover" works but does not help. "mount -o recovery" does not help This happens with all kernels I tried: 3.16, 3.16.7-ctk7, 3.18.9, 3.19.1, 4.0-rc2 Regards, Martin PS: I attach the relevant part of syslog.
Mar 8 14:21:22 zertz kernel: Btrfs loaded Mar 8 14:21:22 zertz kernel: BTRFS: device label raid1_20130919 devid 2 transid 7634 /dev/sdb Mar 8 14:21:24 zertz kernel: scsi 7:0:0:0: Direct-Access TOSHIBA External USB 3.0 0201 PQ: 0 ANSI: 6 Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: Attached scsi generic sg3 type 0 Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: [sdc] 976773164 512-byte logical blocks: (500 GB/465 GiB) Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: [sdc] Write Protect is off Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: [sdc] Mode Sense: 2f 00 00 00 Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA Mar 8 14:21:24 zertz kernel: sd 7:0:0:0: [sdc] Attached SCSI disk Mar 8 14:21:24 zertz kernel: BTRFS: device label raid1_20130919 devid 1 transid 7634 /dev/sdc ........... Mar 8 14:28:34 zertz kernel: BTRFS info (device sdc): enabling auto recovery Mar 8 14:28:34 zertz kernel: BTRFS info (device sdc): disk space caching is enabled Mar 8 14:28:34 zertz kernel: BTRFS: has skinny extents Mar 8 14:28:34 zertz kernel: BTRFS: bdev /dev/sdc errs: wr 463411, rd 369202, flush 0, corrupt 92081, gen 452 Mar 8 14:28:34 zertz kernel: BTRFS: bdev /dev/sdb errs: wr 35219, rd 0, flush 12, corrupt 0, gen 149 ........... Mar 8 14:41:09 zertz kernel: BTRFS info (device sdc): enabling inode map caching Mar 8 14:41:09 zertz kernel: BTRFS info (device sdc): disk space caching is enabled Mar 8 14:41:09 zertz kernel: BTRFS: has skinny extents Mar 8 14:41:09 zertz kernel: BTRFS: bdev /dev/sdc errs: wr 463411, rd 369202, flush 0, corrupt 92081, gen 452 Mar 8 14:41:09 zertz kernel: BTRFS: bdev /dev/sdb errs: wr 35219, rd 0, flush 12, corrupt 0, gen 149 ........... Mar 8 14:41:50 zertz kernel: BTRFS info (device sdc): leaf 647632838656 total ptrs 35 free space 1365 Mar 8 14:41:50 zertz kernel: item 0 key (256 1 0) itemoff 3835 itemsize 160 Mar 8 14:41:50 zertz kernel: inode generation 3 size 334 mode 40755 Mar 8 14:41:50 zertz kernel: item 1 key (256 12 256) itemoff 3823 itemsize 12 Mar 8 14:41:50 zertz kernel: item 2 key (256 84 372899056) itemoff 3777 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1113 type 2 Mar 8 14:41:50 zertz kernel: item 3 key (256 84 1204775058) itemoff 3731 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1123 type 2 Mar 8 14:41:50 zertz kernel: item 4 key (256 84 1739351263) itemoff 3687 itemsize 44 Mar 8 14:41:50 zertz kernel: dir oid 260 type 1 Mar 8 14:41:50 zertz kernel: item 5 key (256 84 2255550154) itemoff 3641 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1111 type 2 Mar 8 14:41:50 zertz kernel: item 6 key (256 84 2355380432) itemoff 3604 itemsize 37 Mar 8 14:41:50 zertz kernel: dir oid 1052 type 2 Mar 8 14:41:50 zertz kernel: item 7 key (256 84 2403767336) itemoff 3569 itemsize 35 Mar 8 14:41:50 zertz kernel: dir oid 635 type 2 Mar 8 14:41:50 zertz kernel: item 8 key (256 84 2411687327) itemoff 3523 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1110 type 2 Mar 8 14:41:50 zertz kernel: item 9 key (256 84 2988794070) itemoff 3477 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1094 type 2 Mar 8 14:41:50 zertz kernel: item 10 key (256 84 3101767096) itemoff 3442 itemsize 35 Mar 8 14:41:50 zertz kernel: dir oid 1060 type 2 Mar 8 14:41:50 zertz kernel: item 11 key (256 84 3273002227) itemoff 3404 itemsize 38 Mar 8 14:41:50 zertz kernel: dir oid 1093 type 2 Mar 8 14:41:50 zertz kernel: item 12 key (256 84 3622448984) itemoff 3369 itemsize 35 Mar 8 14:41:50 zertz kernel: dir oid 258 type 2 Mar 8 14:41:50 zertz kernel: item 13 key (256 84 3727333104) itemoff 3332 itemsize 37 Mar 8 14:41:50 zertz kernel: dir oid 636 type 2 Mar 8 14:41:50 zertz kernel: item 14 key (256 84 3784571614) itemoff 3282 itemsize 50 Mar 8 14:41:50 zertz kernel: dir oid 1122 type 2 Mar 8 14:41:50 zertz kernel: item 15 key (256 84 3951646248) itemoff 3236 itemsize 46 Mar 8 14:41:50 zertz kernel: dir oid 1062 type 2 Mar 8 14:41:50 zertz kernel: item 16 key (256 96 2) itemoff 3201 itemsize 35 Mar 8 14:41:50 zertz kernel: item 17 key (256 96 9) itemoff 3166 itemsize 35 Mar 8 14:41:50 zertz kernel: item 18 key (256 96 10) itemoff 3129 itemsize 37 Mar 8 14:41:50 zertz kernel: item 19 key (256 96 17) itemoff 3092 itemsize 37 Mar 8 14:41:50 zertz kernel: item 20 key (256 96 22) itemoff 3057 itemsize 35 Mar 8 14:41:50 zertz kernel: item 21 key (256 96 23) itemoff 3011 itemsize 46 Mar 8 14:41:50 zertz kernel: item 22 key (256 96 25) itemoff 2973 itemsize 38 Mar 8 14:41:50 zertz kernel: item 23 key (256 96 27) itemoff 2927 itemsize 46 Mar 8 14:41:50 zertz kernel: item 24 key (256 96 31) itemoff 2881 itemsize 46 Mar 8 14:41:50 zertz kernel: item 25 key (256 96 33) itemoff 2835 itemsize 46 Mar 8 14:41:50 zertz kernel: item 26 key (256 96 35) itemoff 2789 itemsize 46 Mar 8 14:41:50 zertz kernel: item 27 key (256 96 36) itemoff 2745 itemsize 44 Mar 8 14:41:50 zertz kernel: item 28 key (256 96 38) itemoff 2695 itemsize 50 Mar 8 14:41:50 zertz kernel: item 29 key (256 96 39) itemoff 2649 itemsize 46 Mar 8 14:41:50 zertz kernel: item 30 key (260 1 0) itemoff 2489 itemsize 160 Mar 8 14:41:50 zertz kernel: inode generation 7445 size 3 mode 100644 Mar 8 14:41:50 zertz kernel: item 31 key (260 12 256) itemoff 2465 itemsize 24 Mar 8 14:41:50 zertz kernel: item 32 key (260 108 0) itemoff 2441 itemsize 24 Mar 8 14:41:50 zertz kernel: inline extent data size 3 Mar 8 14:41:50 zertz kernel: item 33 key (18446744073709551604 1 0) itemoff 2281 itemsize 160 Mar 8 14:41:50 zertz kernel: inode generation 0 size 0 mode 100600 Mar 8 14:41:50 zertz kernel: item 34 key (18446744073709551605 0 0) itemoff 2240 itemsize 41 Mar 8 14:41:50 zertz kernel: BTRFS critical (device sdc): unable to update root key 5 132 0 Mar 8 14:41:50 zertz kernel: ------------[ cut here ]------------ Mar 8 14:41:50 zertz kernel: kernel BUG at fs/btrfs/root-tree.c:160! Mar 8 14:41:50 zertz kernel: invalid opcode: 0000 [#1] SMP Mar 8 14:41:50 zertz kernel: Modules linked in: usblp btrfs xor zlib_deflate raid6_pq sg uas usb_storage ctr ccm nf_log_ipv4 nf_log_common xt_LOG ipt_REJECT nf_reject_ipv4 xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack iptable_filter ip_tables x_tables arc4 iwldvm snd_hda_codec_conexant snd_hda_codec_generic mac80211 aesni_intel snd_hda_intel iwlwifi aes_x86_64 snd_hda_controller cfg80211 snd_hda_codec ehci_pci glue_helper lrw snd_pcm_oss gf128mul snd_mixer_oss ablk_helper snd_pcm cryptd snd_timer ehci_hcd usbcore usb_common [last unloaded: pps_core] Mar 8 14:41:50 zertz kernel: CPU: 1 PID: 9195 Comm: btrfs-transacti Tainted: G U 4.0.0-rc2-00343-g6498f43 #77 Mar 8 14:41:50 zertz kernel: Hardware name: LENOVO 4349WK7/4349WK7, BIOS 6MET81WW (1.41 ) 10/26/2010 Mar 8 14:41:50 zertz kernel: task: ffff88008fda07d0 ti: ffff8801334e0000 task.ti: ffff8801334e0000 Mar 8 14:41:50 zertz kernel: RIP: 0010:[<ffffffffa04959b9>] [<ffffffffa04959b9>] btrfs_update_root+0x88/0x1e0 [btrfs] Mar 8 14:41:50 zertz kernel: RSP: 0018:ffff8801334e3d28 EFLAGS: 00010292 Mar 8 14:41:50 zertz kernel: RAX: 000000000000003e RBX: 0000000000000001 RCX: 0000000000000007 Mar 8 14:41:50 zertz kernel: RDX: 0000000000005353 RSI: 0000000000000246 RDI: ffff880137c8d0e0 Mar 8 14:41:50 zertz kernel: RBP: ffff880066dd9090 R08: 0000000000000000 R09: 0000000000000000 Mar 8 14:41:50 zertz kernel: R10: 0000000000000001 R11: 0000000000aaaaaa R12: ffff880092290800 Mar 8 14:41:50 zertz kernel: R13: ffff880066dc80b0 R14: ffff8800922f41df R15: ffff8800922f4028 Mar 8 14:41:50 zertz kernel: FS: 0000000000000000(0000) GS:ffff880137c80000(0000) knlGS:0000000000000000 Mar 8 14:41:50 zertz kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b Mar 8 14:41:50 zertz kernel: CR2: 00007fdf30234094 CR3: 00000000015a3000 CR4: 00000000000007e0 Mar 8 14:41:50 zertz kernel: Stack: Mar 8 14:41:50 zertz kernel: 0000000000000000 ffffffff81188b3d ffffffff81188626 0000000000000000 Mar 8 14:41:50 zertz kernel: ffff8801254e1ce0 ffff880066dc80b0 ffff88009201c000 ffff88009201c068 Mar 8 14:41:50 zertz kernel: 0000000000000001 ffff8800922f4000 0000000000000001 ffffffffa04fae6d Mar 8 14:41:50 zertz kernel: Call Trace: Mar 8 14:41:50 zertz kernel: [<ffffffff81188b3d>] ? radix_tree_gang_lookup_tag+0xa9/0xbd Mar 8 14:41:50 zertz kernel: [<ffffffff81188626>] ? radix_tree_tag_clear+0x8c/0xeb Mar 8 14:41:50 zertz kernel: [<ffffffffa04fae6d>] ? commit_fs_roots.isra.18+0x10b/0x13a [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffffa0493a89>] ? btrfs_run_delayed_refs+0x174/0x187 [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffffa04a12c1>] ? btrfs_commit_transaction+0x403/0x8d5 [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffffa04a1af8>] ? start_transaction+0x365/0x486 [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffffa049d783>] ? transaction_kthread+0xe1/0x198 [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffffa049d6a2>] ? btrfs_cleanup_transaction+0x38f/0x38f [btrfs] Mar 8 14:41:50 zertz kernel: [<ffffffff8104a020>] ? kthread+0xab/0xb3 Mar 8 14:41:50 zertz kernel: [<ffffffff81040000>] ? get_signal+0x2e0/0x4ce Mar 8 14:41:50 zertz kernel: [<ffffffff81049f75>] ? __kthread_parkme+0x5d/0x5d Mar 8 14:41:50 zertz kernel: [<ffffffff813d5cc8>] ? ret_from_fork+0x58/0x90 Mar 8 14:41:50 zertz kernel: [<ffffffff81049f75>] ? __kthread_parkme+0x5d/0x5d Mar 8 14:41:50 zertz kernel: Code: 00 4c 89 e7 e8 22 f2 ff ff 41 0f b6 4e 08 49 8b bc 24 f0 01 00 00 48 c7 c6 ef ed 4f a0 4d 8b 46 09 49 8b 16 31 c0 e8 c5 93 fe ff <0f> 0b 8b 55 40 48 8b 45 00 89 d6 48 89 c7 89 54 24 0c 48 89 04 Mar 8 14:41:50 zertz kernel: RIP [<ffffffffa04959b9>] btrfs_update_root+0x88/0x1e0 [btrfs] Mar 8 14:41:50 zertz kernel: RSP <ffff8801334e3d28> Mar 8 14:41:50 zertz kernel: ---[ end trace b334c2b2361eb394 ]---
