Hello! Since my system was temporarily overloaded (load 500+ for probably several hours but it recovered, no reboot needed), I'm seeing btrfs-related backtraces in dmesg with the fs going RO. I tried to fix it but it fails: > Fixed 0 roots. > checking extents > ref mismatch on [3043919785984 57344] extent item 1, found 3 > Data backref 3043919785984 root 265 owner 83535 offset 131072 num_refs 0 not found in extent tree > Incorrect local backref count on 3043919785984 root 265 owner 83535 offset 131072 found 1 wanted 0 back 0x61854760 > Backref disk bytenr does not match extent record, bytenr=3043919785984, ref bytenr=3043919790080 > Backref bytes do not match extent backref, bytenr=3043919785984, ref bytes=57344, backref bytes=40960 > Data backref 3043919785984 root 259 owner 11522804 offset 0 num_refs 0 not found in extent tree > Incorrect local backref count on 3043919785984 root 259 owner 11522804 offset 0 found 1 wanted 0 back 0x57892430 > Backref disk bytenr does not match extent record, bytenr=3043919785984, ref bytenr=3043919831040 > Backref bytes do not match extent backref, bytenr=3043919785984, ref bytes=57344, backref bytes=8192 > backpointer mismatch on [3043919785984 57344] > attempting to repair backref discrepency for bytenr 3043919785984 > Ref doesn't match the record start and is compressed, please take a btrfs-image of this file system and send it to a btrfs developer so they can complete this functionality for bytenr 3043919790080 > failed to repair damaged filesystem, aborting > enabling repair mode > Checking filesystem on /dev/bcacache48 8 UUID: > bc201ce5-8f2b-4263-995a-6641e89d4c88 When I identify the files with "btrfs inspect-internal" and try to delete them, btrfs fails and goes into RO mode: [ 735.877040] ------------[ cut here ]------------ [ 735.877048] WARNING: CPU: 2 PID: 809 at fs/btrfs/extent-tree.c:7053 __btrfs_free_extent.isra.71+0x740/0xbc0 [ 735.877049] Modules linked in: uas usb_storage r8168(O) nvidia_drm(PO) vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) nvidia_uvm(PO) nvidia_modeset(PO) nvidia(PO) nct6775 hwmon_vid coretemp hwmon efivarfs [ 735.877065] CPU: 2 PID: 809 Comm: umount Tainted: P O 4.14.0-pf4 #1 [ 735.877066] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z68 Pro3, BIOS L2.16A 02/22/2013 [ 735.877067] task: ffff88040b6cf080 task.stack: ffffc900035b0000 [ 735.877070] RIP: 0010:__btrfs_free_extent.isra.71+0x740/0xbc0 [ 735.877071] RSP: 0018:ffffc900035b3c00 EFLAGS: 00010246 [ 735.877073] RAX: 00000000fffffffe RBX: 000002c4b7c20000 RCX: ffffc900035b3bb8 [ 735.877074] RDX: 000002c4b7c2d000 RSI: ffff88021c22f607 RDI: ffffc900035b3bb8 [ 735.877075] RBP: 00000000fffffffe R08: 0000000000000000 R09: 000000000001464f [ 735.877076] R10: 0000000000020000 R11: 000000000000076d R12: ffff880414618000 [ 735.877077] R13: ffff880406b3d850 R14: 0000000000000000 R15: 0000000000000109 [ 735.877079] FS: 00007f6d13424780(0000) GS:ffff88042f280000(0000) knlGS:0000000000000000 [ 735.877080] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 735.877081] CR2: 0000003d9afb3730 CR3: 000000017b391002 CR4: 00000000001606e0 [ 735.877082] Call Trace: [ 735.877090] __btrfs_run_delayed_refs+0x3de/0x1000 [ 735.877094] btrfs_run_delayed_refs+0x75/0x240 [ 735.877098] btrfs_commit_transaction+0x31/0x820 [ 735.877102] ? btrfs_attach_transaction_barrier+0x19/0x40 [ 735.877105] sync_filesystem+0x65/0x80 [ 735.877109] generic_shutdown_super+0x1d/0x110 [ 735.877111] kill_anon_super+0x9/0x10 [ 735.877115] btrfs_kill_super+0xd/0x90 [ 735.877118] deactivate_locked_super+0x34/0x60 [ 735.877121] cleanup_mnt+0x36/0x70 [ 735.877126] task_work_run+0x84/0xa0 [ 735.877128] exit_to_usermode_loop+0x81/0x90 [ 735.877131] syscall_return_slowpath+0x7b/0xa0 [ 735.877135] entry_SYSCALL_64_fastpath+0x92/0x94 [ 735.877138] RIP: 0033:0x3d9acf94b7 [ 735.877139] RSP: 002b:00007ffe139c98a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 [ 735.877141] RAX: 0000000000000000 RBX: 0000000001094260 RCX: 0000003d9acf94b7 [ 735.877142] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001094440 [ 735.877143] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffe139c87c8 [ 735.877144] R10: 0000000000000073 R11: 0000000000000202 R12: 0000000001094440 [ 735.877145] R13: 000000349aa55e84 R14: 0000000000000001 R15: 0000000000000000 [ 735.877146] Code: ff 4d 89 fd 41 bf 4c 00 00 00 e9 d8 fc ff ff 48 8b 3c 24 4d 89 f9 4d 89 f0 48 89 d9 4c 89 ea e8 57 b1 ff ff 89 c5 e9 51 fc ff ff <0f> ff 49 8b 7d 00 e8 f5 b7 00 00 4d 89 f8 4c 89 f1 48 89 da ff [ 735.877180] ---[ end trace 5c0765d6f8b69164 ]--- Full dmesg is located here: https://gist.github.com/kakra/82bc726457ee4d401162195d5da1357b It also includes a second dmesg log (20171209) which occurred during normal operation when the system tried to access the affected files. -- Regards, Kai Replies to list-only preferred. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
