syzbot


INFO: task hung in btrfs_commit_transaction_async

Status: auto-obsoleted due to no activity on 2023/07/23 02:14
Subsystems: btrfs
[Documentation on labels]
First crash: 776d, last: 645d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in btrfs_commit_transaction_async (2) btrfs 1 429d 429d 0/28 auto-obsoleted due to no activity on 2024/02/24 21:48

Sample crash report:
INFO: task syz-executor.0:12745 blocked for more than 143 seconds.
      Not tainted 6.3.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:24280 pid:12745 ppid:5124   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5307 [inline]
 __schedule+0x173b/0x4630 kernel/sched/core.c:6625
 schedule+0xc3/0x180 kernel/sched/core.c:6701
 btrfs_commit_transaction_async+0x2e3/0x450 fs/btrfs/transaction.c:1971
 btrfs_ioctl_start_sync+0xe6/0x1f0 fs/btrfs/ioctl.c:3124
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fdc7ea8c169
RSP: 002b:00007fdc761bc168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdc7ebac120 RCX: 00007fdc7ea8c169
RDX: 0000000020000140 RSI: 0000000080089418 RDI: 0000000000000004
RBP: 00007fdc7eae7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc676a03df R14: 00007fdc761bc300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cf25570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cf25d70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffffffff8cf253a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/4747:
 #0: ffff8880285c4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900015902f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2177
1 lock held by syz-executor.3/5104:
 #0: 
ffff8880290de0e0 (&type->s_umount_key#73){+.+.}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:361
1 lock held by syz-executor.2/5117:
 #0: ffff888021b8e0e0 (&type->s_umount_key#77){++++}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:361
2 locks held by kworker/0:17/5871:
 #0: ffff888012470d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363
 #1: ffffc90015817d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365
2 locks held by kworker/0:32/11048:
 #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363
 #1: ffffc90014f37d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365
2 locks held by syz-executor.0/15186:

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x187/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xec2/0xf00 kernel/hung_task.c:379
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5239 Comm: kworker/u4:8 Not tainted 6.3.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:kasan_check_range+0x5/0x290 mm/kasan/generic.c:186
Code: 01 c6 48 89 c7 e8 9b 14 bf 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 0f 1f 84 00 00 00 00 00 66 0f 1f 00 55 <41> 57 41 56 53 b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5
RSP: 0018:ffffc9000476f790 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff816a1564
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e534aa8
RBP: ffffc9000476f8e8 R08: 0000000000000001 R09: 0000000000000000
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff920008edefc
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f56aedabf84 CR3: 000000001ee09000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 cpumask_test_cpu include/linux/cpumask.h:504 [inline]
 cpu_online include/linux/cpumask.h:1082 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xd4/0x520 kernel/locking/lockdep.c:5640
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 debug_object_activate+0x9a/0x6d0 lib/debugobjects.c:665
 debug_timer_activate kernel/time/timer.c:782 [inline]
 __mod_timer+0x938/0xf40 kernel/time/timer.c:1119
 queue_delayed_work_on+0x15a/0x260 kernel/workqueue.c:1708
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2390
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537
 kthread+0x270/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/24 02:10 upstream 457391b03803 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in btrfs_commit_transaction_async
2023/01/25 10:46 upstream fb6e71db53f3 9dfcf09c .config console log report info ci2-upstream-fs INFO: task hung in btrfs_commit_transaction_async
2022/12/14 10:31 upstream 02bf43c7b7f7 f6511626 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in btrfs_commit_transaction_async
* Struck through repros no longer work on HEAD.