syzbot


INFO: task hung in __writeback_inodes_sb_nr (2)

Status: auto-obsoleted due to no activity on 2023/02/27 15:30
Reported-by: syzbot+5c28d141082d2c22172f@syzkaller.appspotmail.com
First crash: 626d, last: 625d
Similar bugs (13)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in __writeback_inodes_sb_nr fs 53 2009d 2272d 0/27 closed as dup on 2018/09/08 15:33
android-49 INFO: task hung in __writeback_inodes_sb_nr 26 2106d 2249d 0/3 auto-closed as invalid on 2019/04/08 13:33
android-414 INFO: task hung in __writeback_inodes_sb_nr 1 2044d 1920d 0/1 auto-closed as invalid on 2019/06/09 16:55
upstream INFO: task hung in __writeback_inodes_sb_nr (5) ext4 C done 48 514d 885d 22/27 fixed on 2023/02/24 13:50
linux-5.15 INFO: task hung in __writeback_inodes_sb_nr origin:lts-only C done 1496 86d 494d 0/3 upstream: reported C repro on 2023/03/09 17:32
linux-6.1 INFO: task hung in __writeback_inodes_sb_nr (2) origin:lts-only C 6 9d06h 199d 0/3 upstream: reported C repro on 2023/12/30 04:30
linux-4.19 INFO: task hung in __writeback_inodes_sb_nr ext4 4 509d 656d 0/1 upstream: reported on 2022/09/28 21:19
linux-6.1 INFO: task hung in __writeback_inodes_sb_nr 1 333d 333d 0/3 auto-obsoleted due to no activity on 2023/11/26 06:37
upstream INFO: task hung in __writeback_inodes_sb_nr (6) bcachefs C done 918 9h29m 395d 1/27 upstream: reported C repro on 2023/06/17 00:33
upstream INFO: task hung in __writeback_inodes_sb_nr (4) ext4 4 893d 947d 0/27 closed as invalid on 2022/02/08 10:10
upstream INFO: task hung in __writeback_inodes_sb_nr (3) ext4 2 1159d 1257d 0/27 auto-closed as invalid on 2021/08/11 17:49
upstream INFO: task hung in __writeback_inodes_sb_nr (2) ext4 1 1441d 1441d 0/27 auto-closed as invalid on 2020/11/03 06:13
linux-4.14 INFO: task hung in __writeback_inodes_sb_nr 1 1507d 1507d 0/1 auto-closed as invalid on 2020/09/27 19:31

Sample crash report:
F2FS-fs (loop1): sanity_check_inode: inode (ino=8) has corrupted i_extra_isize: 36, max: 12
F2FS-fs (loop1): sanity_check_inode: inode (ino=8) has corrupted i_extra_isize: 36, max: 12
F2FS-fs (loop1): sanity_check_inode: inode (ino=8) has corrupted i_extra_isize: 36, max: 12
INFO: task syz-executor.1:7999 blocked for more than 140 seconds.
      Not tainted 4.14.296-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D24096  7999      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 wb_wait_for_completion fs/fs-writeback.c:222 [inline]
 wb_wait_for_completion+0x118/0x170 fs/fs-writeback.c:218
 __writeback_inodes_sb_nr+0x164/0x1d0 fs/fs-writeback.c:2343
 __sync_filesystem fs/sync.c:36 [inline]
 sync_filesystem fs/sync.c:64 [inline]
 sync_filesystem+0x8c/0x230 fs/sync.c:48
 generic_shutdown_super+0x70/0x370 fs/super.c:432
 kill_block_super+0x95/0xe0 fs/super.c:1161
 deactivate_locked_super+0x6c/0xd0 fs/super.c:319
 deactivate_super+0x7f/0xa0 fs/super.c:350
 cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f90d466aa17
RSP: 002b:00007ffc22891188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f90d466aa17
RDX: 00007ffc22891259 RSI: 000000000000000a RDI: 00007ffc22891250
RBP: 00007ffc22891250 R08: 00000000ffffffff R09: 00007ffc22891020
R10: 0000555555dae903 R11: 0000000000000246 R12: 00007f90d46c3826
R13: 00007ffc22892310 R14: 0000555555dae810 R15: 00007ffc22892350

Showing all locks held in the system:
1 lock held by khungtaskd/1515:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff87028579>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by syz-executor.1/7999:
 #0:  (&type->s_umount_key#63){++++}, at: [<ffffffff81877187>] deactivate_super+0x77/0xa0 fs/super.c:349

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1515 Comm: khungtaskd Not tainted 4.14.296-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.296-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Workqueue: writeback wb_workfn (flush-7:1)
task: ffff8880b55f65c0 task.stack: ffff8880b5600000
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:60
RSP: 0018:ffff8880b5607138 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: fffffbfff17d9db8
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000282
RBP: ffff8880983c2388 R08: ffff8880b55f65c0 R09: dffffc0000000000
R10: 0000000000000000 R11: ffff8880b55f65c0 R12: 0000000000000200
R13: ffff888098712500 R14: dffffc0000000000 R15: ffff8880983fc55c
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0243d90020 CR3: 00000000b3451000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 gc_data_segment fs/f2fs/gc.c:818 [inline]
 do_garbage_collect+0x1a59/0x38f0 fs/f2fs/gc.c:978
 f2fs_gc+0x7db/0x1eb0 fs/f2fs/gc.c:1060
 f2fs_balance_fs+0x423/0x5a0 fs/f2fs/segment.c:436
 __write_data_page+0x646/0x1480 fs/f2fs/data.c:1615
 f2fs_write_cache_pages+0x40d/0xe50 fs/f2fs/data.c:1744
 __f2fs_write_data_pages+0x2e2/0xb90 fs/f2fs/data.c:1838
 do_writepages+0xc3/0x240 mm/page-writeback.c:2361
 __writeback_single_inode+0xda/0x1010 fs/fs-writeback.c:1382
 writeback_sb_inodes+0x48b/0xd30 fs/fs-writeback.c:1645
 wb_writeback+0x243/0xb80 fs/fs-writeback.c:1820
 wb_do_writeback fs/fs-writeback.c:1952 [inline]
 wb_workfn+0x2bd/0xf50 fs/fs-writeback.c:1988
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: ff ff 48 89 df e8 e1 bd 29 00 e9 9f fe ff ff 4c 89 e7 e8 d4 bd 29 00 e9 2c fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <65> 48 8b 04 25 c0 7f 02 00 48 85 c0 74 1a 65 8b 15 7b 37 ad 7e 

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/30 15:29 linux-4.14.y 41f36d7859a7 2a71366b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in __writeback_inodes_sb_nr
2022/10/29 04:06 linux-4.14.y 41f36d7859a7 899d812a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in __writeback_inodes_sb_nr
* Struck through repros no longer work on HEAD.