Re: [btrfs_put_block_group] WARNING: CPU: 1 PID: 14674 at fs/btrfs/disk-io.c:3675 free_fs_root+0xc2/0xd0 [btrfs]

From: Nikolay Borisov
Date: Thu Apr 19 2018 - 03:25:42 EST



On 19.04.2018 08:32, Fengguang Wu wrote:
> Hello,
>
> FYI this happens in mainline kernel and at least dates back to v4.16 .
>
> It's rather rare error and happens when running xfstests.

Yeah, so this is something which only recently was characterised as
leaking delalloc inodes. I can easily reproduce this when running
generic/019 test. A fix is in the works.

>
> [ 438.327552] BTRFS: error (device dm-0) in __btrfs_free_extent:6962: errno=-5 IO failure
> [ 438.336415] BTRFS: error (device dm-0) in btrfs_run_delayed_refs:3070: errno=-5 IO failure
> [ 438.345590] BTRFS error (device dm-0): pending csums is 1028096
> [ 438.369254] BTRFS error (device dm-0): cleaner transaction attach returned -30
> [ 438.377674] BTRFS info (device dm-0): at unmount delalloc count 98304
> [ 438.385166] WARNING: CPU: 1 PID: 14674 at fs/btrfs/disk-io.c:3675 free_fs_root+0xc2/0xd0 [btrfs]
> [ 438.396562] Modules linked in: dm_snapshot dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio dm_flakey dm_mod netconsole btrfs xor zstd_decompress zstd_compress xxhash raid6_pq sd_mod sg snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic ata_generic pata_acpi intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel kvm_intel snd_hda_codec kvm irqbypass crct10dif_pclmul eeepc_wmi crc32_pclmul crc32c_intel ghash_clmulni_intel pata_via asus_wmi sparse_keymap snd_hda_core ata_piix snd_hwdep ppdev rfkill wmi_bmof i915 pcbc snd_pcm snd_timer drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops snd aesni_intel parport_pc crypto_simd pcspkr libata soundcore cryptd glue_helper drm wmi parport video shpchp ip_tables
> [ 438.467607] CPU: 1 PID: 14674 Comm: umount Not tainted 4.17.0-rc1 #1
> [ 438.474798] Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 1002 04/01/2011
> [ 438.484804] RIP: 0010:free_fs_root+0xc2/0xd0 [btrfs]
> [ 438.490590] RSP: 0018:ffffc90008b0fda8 EFLAGS: 00010282
> [ 438.496641] RAX: ffff88017c5954b0 RBX: ffff880137f6d800 RCX: 0000000180100003
> [ 438.504652] RDX: 0000000000000001 RSI: ffffea0006e93600 RDI: 0000000000000000
> [ 438.512679] RBP: ffff88017b360000 R08: ffff8801ba4dd000 R09: 0000000180100003
> [ 438.520644] R10: ffffc90008b0fc70 R11: 0000000000000000 R12: ffffc90008b0fdd0
> [ 438.528657] R13: ffff88017b360080 R14: ffffc90008b0fdc8 R15: 0000000000000000
> [ 438.536662] FS: 00007f06c1a80fc0(0000) GS:ffff8801bfa80000(0000) knlGS:0000000000000000
> [ 438.545582] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 438.552157] CR2: 00007f06c12b0260 CR3: 000000017d3de004 CR4: 00000000000606e0
> [ 438.642653] RAX: 0000000000000000 RBX: 000000000234a2d0 RCX: 00007f06c1359cf7
> [ 438.793559] CPU: 1 PID: 14674 Comm: umount Tainted: G W 4.17.0-rc1 #1
> [ 438.802152] Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 1002 04/01/2011
> [ 438.812108] RIP: 0010:btrfs_put_block_group+0x41/0x60 [btrfs]
> [ 438.819364] RSP: 0018:ffffc90008b0fde0 EFLAGS: 00010206
> [ 438.825378] RAX: 0000000000000000 RBX: ffff8801abf63000 RCX: e38e38e38e38e38f
> [ 438.833307] RDX: 0000000000000001 RSI: 00000000000009f6 RDI: ffff8801abf63000
> [ 438.841230] RBP: ffff88017b360000 R08: ffff88017d3b7750 R09: 0000000180380010
> [ 438.849133] R10: ffffc90008b0fca0 R11: 0000000000000000 R12: ffff8801abf63000
> [ 438.857047] R13: ffff88017b3600a0 R14: ffff8801abf630e0 R15: dead000000000100
> [ 438.864943] FS: 00007f06c1a80fc0(0000) GS:ffff8801bfa80000(0000) knlGS:0000000000000000
> [ 438.873793] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 438.880320] CR2: 00007f06c12b0260 CR3: 000000017d3de004 CR4: 00000000000606e0
> [ 438.888226] Call Trace:
> [ 438.891454] btrfs_free_block_groups+0x138/0x3d0 [btrfs]
> [ 438.897569] close_ctree+0x13b/0x2f0 [btrfs]
> [ 438.902618] generic_shutdown_super+0x6c/0x120:
> __read_once_size at include/linux/compiler.h:188
> (inlined by) list_empty at include/linux/list.h:203
> (inlined by) generic_shutdown_super at fs/super.c:442
> [ 438.907801] kill_anon_super+0xe/0x20:
> kill_anon_super at fs/super.c:1038
> [ 438.912223] btrfs_kill_super+0x13/0x100 [btrfs]
> [ 438.917598] deactivate_locked_super+0x3f/0x70:
> deactivate_locked_super at fs/super.c:320
> [ 438.922757] cleanup_mnt+0x3b/0x70:
> cleanup_mnt at fs/namespace.c:1174
> [ 438.926879] task_work_run+0xa3/0xe0:
> task_work_run at kernel/task_work.c:115 (discriminator 1)
> [ 438.931205] exit_to_usermode_loop+0x9e/0xa0:
> tracehook_notify_resume at include/linux/tracehook.h:191
> (inlined by) exit_to_usermode_loop at arch/x86/entry/common.c:166
> [ 438.936226] do_syscall_64+0x16c/0x180:
> prepare_exit_to_usermode at arch/x86/entry/common.c:196
> (inlined by) syscall_return_slowpath at arch/x86/entry/common.c:265
> (inlined by) do_syscall_64 at arch/x86/entry/common.c:290
> [ 438.940717] entry_SYSCALL_64_after_hwframe+0x44/0xa9:
> entry_SYSCALL_64_after_hwframe at arch/x86/entry/entry_64.S:247
> [ 438.946507] RIP: 0033:0x7f06c1359cf7
> [ 438.950798] RSP: 002b:00007ffc6a59c608 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
> [ 438.959137] RAX: 0000000000000000 RBX: 000000000234a2d0 RCX: 00007f06c1359cf7
> [ 438.967056] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000234a4b0
> [ 438.974937] RBP: 000000000234a4b0 R08: 0000000000000005 R09: 000000000234b510
> [ 438.982801] R10: 00000000000006f4 R11: 0000000000000246 R12: 00007f06c1865e44
> [ 438.990695] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffc6a59c890
> [ 438.998600] Code: 2a 48 8b 83 e8 01 00 00 48 85 c0 75 2c 48 8b bb d8 00 00 00 e8 c1 1e b8 e0 48 89 df 5b e9 b8 1e b8 e0 0f 0b 48 83 7b 50 00 74 d6 <0f> 0b 48 8b 83 e8 01 00 00 48 85 c0 74 d4 0f 0b eb d0 0f 1f 00
> [ 439.019082] ---[ end trace 9263ab2c46fd437a ]---
> [ 439.030057] WARNING: CPU: 2 PID: 14674 at fs/btrfs/extent-tree.c:9898 btrfs_free_block_groups+0x2a2/0x3d0 [btrfs]
>
> Attached the full dmesg, kconfig and reproduce scripts.
>
> Thanks,
> Fengguang
>