syzbot


INFO: task hung in __writeback_inodes_sb_nr (6)

Status: upstream: reported C repro on 2023/06/17 00:33
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+38d04642cea49f3a3d2e@syzkaller.appspotmail.com
Fix commit: PM: hibernate: Fix block device handling in test_resume mode
Patched on: [ci-upstream-linux-next-kasan-gce-root], missing on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb]
First crash: 698d, last: 10d
Cause bisection: introduced by (bisect log) :
commit 5904de0d735bbb3b4afe9375c5b4f9748f882945
Author: Chen Yu <yu.c.chen@intel.com>
Date: Fri Apr 14 12:10:42 2023 +0000

  PM: hibernate: Do not get block device exclusively in test_resume mode

Crash: INFO: rcu detected stall in corrupted (log)
Repro: C syz .config
  
Discussions (4)
Title Replies (including bot) Last reply
[PATCH v2 2/2] PM: hibernate: Fix the exclusive get block device in test_resume mode 2 (2) 2023/09/06 05:27
[PATCH] PM: hibernate: Fix the exclusive get block device in test_resume mode 3 (3) 2023/08/23 16:13
[syzbot] [ext4?] INFO: task hung in __writeback_inodes_sb_nr (6) 1 (4) 2023/08/18 16:50
[syzbot] Monthly ext4 report (Aug 2023) 0 (1) 2023/08/07 07:27
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 2221d 2484d 0/28 closed as dup on 2018/09/08 15:33
android-49 INFO: task hung in __writeback_inodes_sb_nr 26 2318d 2461d 0/3 auto-closed as invalid on 2019/04/08 13:33
android-414 INFO: task hung in __writeback_inodes_sb_nr 1 2255d 2132d 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 726d 1097d 22/28 fixed on 2023/02/24 13:50
linux-5.15 INFO: task hung in __writeback_inodes_sb_nr origin:lts-only C done 1496 20d 706d 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 error 23 8d10h 411d 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 721d 868d 0/1 upstream: reported on 2022/09/28 21:19
linux-6.1 INFO: task hung in __writeback_inodes_sb_nr 1 545d 545d 0/3 auto-obsoleted due to no activity on 2023/11/26 06:37
upstream INFO: task hung in __writeback_inodes_sb_nr (4) ext4 4 1105d 1159d 0/28 closed as invalid on 2022/02/08 10:10
upstream INFO: task hung in __writeback_inodes_sb_nr (3) ext4 2 1371d 1469d 0/28 auto-closed as invalid on 2021/08/11 17:49
linux-4.14 INFO: task hung in __writeback_inodes_sb_nr (2) 2 837d 838d 0/1 auto-obsoleted due to no activity on 2023/02/27 15:30
upstream INFO: task hung in __writeback_inodes_sb_nr (2) ext4 1 1653d 1653d 0/28 auto-closed as invalid on 2020/11/03 06:13
linux-4.14 INFO: task hung in __writeback_inodes_sb_nr 1 1719d 1719d 0/1 auto-closed as invalid on 2020/09/27 19:31

Sample crash report:
INFO: task syz-executor101:5327 blocked for more than 143 seconds.
      Not tainted 6.12.0-rc5-syzkaller-00181-g6c52d4da1c74 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor101 state:D stack:23072 pid:5327  tgid:5327  ppid:5325   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6782
 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216
 __writeback_inodes_sb_nr+0x2d2/0x380 fs/fs-writeback.c:2713
 sync_filesystem+0xa4/0x230 fs/sync.c:54
 generic_shutdown_super+0x72/0x2d0 fs/super.c:621
 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2278
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c2faf0677
RSP: 002b:00007ffc51f5dc88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00000000000353eb RCX: 00007f3c2faf0677
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc51f5dd40
RBP: 00007ffc51f5dd40 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffc51f5eda0
R13: 000055556d96e6c0 R14: 0000000000000001 R15: 431bde82d7b634db
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u4:0/11:
 #0: ffff88801ac79148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801ac79148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffff88801fc28948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987
1 lock held by khungtaskd/25:
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
2 locks held by kworker/u4:3/41:
 #0: ffff88801c76d148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline]
 #0: ffff88801c76d148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310
 #1: ffffc900005bfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline]
 #1: ffffc900005bfd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310
2 locks held by getty/5109:
 #0: ffff88801fb110a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000039b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz-executor101/5327:
 #0: ffff8880405b60e0 (&type->s_umount_key#43){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880405b60e0 (&type->s_umount_key#43){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880405b60e0 (&type->s_umount_key#43){+.+.}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
2 locks held by bch-copygc/loop/5339:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 25 Comm: khungtaskd Not tainted 6.12.0-rc5-syzkaller-00181-g6c52d4da1c74 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (3804):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/02 02:47 upstream 6c52d4da1c74 f00eed24 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] [mounted in repro] ci-snapshot-upstream-root INFO: task hung in __writeback_inodes_sb_nr
2023/08/16 23:26 upstream 4853c74bd7ab 7773e940 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/02/03 00:25 upstream 69e858e0b8b2 568559e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/20 23:13 upstream 100ceb4817a2 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/20 14:21 upstream ffd294d346d1 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/20 06:14 upstream 9528d418de4d f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/20 00:01 upstream 9528d418de4d f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/19 22:22 upstream 9528d418de4d f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/16 04:15 upstream 619f0b6fad52 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/15 15:05 upstream 619f0b6fad52 7315a7cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/14 17:14 upstream c45323b7560e f310a27d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/14 17:14 upstream c45323b7560e f310a27d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/14 10:53 upstream c45323b7560e b1f1cd88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/14 07:46 upstream c45323b7560e b1f1cd88 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/12 10:30 upstream b62cef9a5c67 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/12 02:32 upstream b62cef9a5c67 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/11 03:50 upstream 2144da25584e 6dbc6a9b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/10 09:30 upstream 2144da25584e 67d7ec0a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/09 16:33 upstream eea6e4b4dfb8 40f46913 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/09 09:49 upstream eea6e4b4dfb8 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/09 05:12 upstream 0b7958fa05d5 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 20:26 upstream 0b7958fa05d5 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 20:25 upstream 0b7958fa05d5 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 16:13 upstream 09a0fa92e5b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 11:26 upstream 09a0fa92e5b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 09:39 upstream 09a0fa92e5b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 07:47 upstream 09a0fa92e5b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/08 01:23 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/07 22:29 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/07 14:56 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/07 06:28 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 18:44 upstream 5428dc1906dd f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 18:20 upstream 5428dc1906dd f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 17:15 upstream 5428dc1906dd f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 15:04 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 11:29 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/06 07:32 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/01/05 18:40 upstream ab75170520d4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2024/06/22 23:23 upstream 35bb670d65fc edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in __writeback_inodes_sb_nr
2024/06/15 18:29 upstream 2ccbdf43d5e7 f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in __writeback_inodes_sb_nr
2023/07/06 06:35 upstream 6cd06ab12d1a ba5dba36 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root INFO: task hung in __writeback_inodes_sb_nr
2023/06/16 11:59 upstream 62d8779610bb f3921d4d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2023/06/13 00:23 upstream fd37b884003c aaed0183 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __writeback_inodes_sb_nr
2023/06/08 02:41 upstream a27648c74210 7086cdb9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2024/12/11 05:47 linux-next af2ea8ab7a54 cfc402b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in __writeback_inodes_sb_nr
2025/02/02 19:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 568559e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/02/01 16:05 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 0dff8567 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/02/01 06:44 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 aa47157c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/31 12:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 4c6ac32f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/22 11:12 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/22 05:49 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/17 23:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 1950a0af2d55 953d1c45 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/16 16:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 6251d1776bc5 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/15 22:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 6251d1776bc5 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/14 20:01 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 6251d1776bc5 7315a7cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
2025/01/07 04:22 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 573067a5a685 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __writeback_inodes_sb_nr
* Struck through repros no longer work on HEAD.