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INFO: task hung in pipe_release (2)

Status: upstream: reported on 2025/06/04 18:15
Reported-by: syzbot+e7195e72b4153b3ec0c9@syzkaller.appspotmail.com
First crash: 11d, last: 11d
▶ ▼ Similar bugs (14)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 INFO: task hung in pipe_release 1 2150d 2150d 0/1 auto-closed as invalid on 2019/11/24 16:38
upstream INFO: task hung in pipe_release (5) fs 160 165d 275d 0/28 auto-obsoleted due to no activity on 2025/02/21 02:48
upstream INFO: task hung in pipe_release (2) ext4 syz done 3 1747d 1778d 15/28 fixed on 2020/09/25 01:17
android-49 INFO: task hung in pipe_release (2) 1 2114d 2114d 0/3 auto-closed as invalid on 2019/12/30 22:08
linux-6.1 INFO: task hung in pipe_release 2 233d 291d 0/3 auto-obsoleted due to no activity on 2025/02/03 06:35
upstream INFO: task hung in pipe_release (4) fs C done 51 705d 705d 23/28 fixed on 2023/10/12 12:48
android-49 INFO: task hung in pipe_release 2 2343d 2255d 0/3 auto-closed as invalid on 2019/07/14 20:38
upstream INFO: task hung in pipe_release (3) fs 4 1308d 1422d 0/28 closed as invalid on 2022/02/07 19:19
upstream INFO: task hung in pipe_release fs 2 2241d 2405d 0/28 auto-closed as invalid on 2019/10/25 10:11
linux-4.19 INFO: task hung in pipe_release 1 1544d 1544d 0/1 auto-closed as invalid on 2021/07/23 11:59
linux-5.15 INFO: task hung in pipe_release 2 240d 302d 0/3 auto-obsoleted due to no activity on 2025/01/27 06:00
linux-5.15 INFO: task hung in pipe_release (2) 1 81d 81d 0/3 upstream: reported on 2025/03/26 20:01
upstream INFO: task hung in pipe_release (6) bcachefs syz done 6 30d 108d 0/28 upstream: reported syz repro on 2025/02/27 19:55
upstream INFO: task can't die in pipe_release (2) fs 1 1600d 1596d 0/28 auto-closed as invalid on 2021/03/29 10:10

Sample crash report:
INFO: task syz.1.2:4344 blocked for more than 143 seconds.
      Not tainted 6.1.141-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2         state:D stack:26240 pid:4344  ppid:4253   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747
 __pipe_lock fs/pipe.c:103 [inline]
 pipe_release+0x4d/0x330 fs/pipe.c:724
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd5a0b8e929
RSP: 002b:00007ffcbef2dc58 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fd5a0db7ba0 RCX: 00007fd5a0b8e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fd5a0db7ba0 R08: 00000000000047dc R09: 00000006bef2df4f
R10: 00007fd5a0db7ac0 R11: 0000000000000246 R12: 000000000001368e
R13: 00007ffcbef2dd50 R14: ffffffffffffffff R15: 00007ffcbef2dd70
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c92b430 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8c92bc50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8c92aaa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
4 locks held by udevd/3624:
2 locks held by getty/4016:
 #0: ffff888030976098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000326b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
1 lock held by syz.1.2/4344:
 #0: ffff888029156468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline]
 #0: ffff888029156468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_release+0x4d/0x330 fs/pipe.c:724
1 lock held by syz.1.2/4347:
 #0: ffff888029156468 (&pipe->mutex/1){+.+.}-{3:3}, at: splice_file_to_pipe+0x2a/0x330 fs/splice.c:1038

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xeee/0xf30 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4257 Comm: syz-executor Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0xb/0x290 mm/kasan/generic.c:189
Code: 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 a4 01 00 00 <41> 57 41 56 53 49 89 f8 49 01 f0 0f 82 57 02 00 00 49 89 f8 49 c1
RSP: 0018:ffffc900001e0a58 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 000000000000002c RCX: ffffffff81630052
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff908b8240
RBP: ffffc900001e0cb0 R08: dffffc0000000000 R09: fffffbfff2117049
R10: fffffbfff2117049 R11: 1ffffffff2117048 R12: 00000000da2e6163
R13: 000000000000402d R14: 0000000034457c0f R15: ffff8880196f2890
FS:  000055556e802500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f652b1b5fa8 CR3: 000000005c14a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 __lock_acquire+0x10b2/0x7c50 kernel/locking/lockdep.c:5045
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 __lock_task_sighand+0x42/0x2d0 kernel/signal.c:1394
 lock_task_sighand include/linux/sched/signal.h:745 [inline]
 do_send_sig_info kernel/signal.c:1300 [inline]
 group_send_sig_info+0x1da/0x250 kernel/signal.c:1449
 do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:840
 irq_work_single+0xd1/0x230 kernel/irq_work.c:211
 irq_work_run_list kernel/irq_work.c:242 [inline]
 irq_work_run+0x152/0x2e0 kernel/irq_work.c:251
 __sysvec_irq_work+0xba/0x350 arch/x86/kernel/irq_work.c:22
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 4f 99 f8 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90004207c90 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: ffffffff8c3d0b78 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52000840f81
R10: fffff52000840f81 R11: 1ffff92000840f80 R12: ffff8880b8f33e01
R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020
 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
 irq_work_queue+0x95/0x140 kernel/irq_work.c:114
 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879
 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886
 bpf_prog_7ba5217f62dcd359+0x38/0x3c
 bpf_dispatcher_nop_func include/linux/bpf.h:1001 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
 bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324
 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
 __traceiter_sys_enter+0x26/0x40 include/trace/events/syscalls.h:18
 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18
 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f127d92ab19
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007ffda8c822c0 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f127e6e4620 RCX: 00007f127d92ab19
RDX: 00007ffda8c822c0 RSI: 00007ffda8c823f0 RDI: 0000000000000011
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f127e6e4670 R15: 0000000000000000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/04 18:14 linux-6.1.y 58485ff1a74f e565f08d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in pipe_release
* Struck through repros no longer work on HEAD.