INFO: task syz.0.636:7964 blocked for more than 140 seconds. Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.636 state:D stack:23072 pid:7964 tgid:7964 ppid:5230 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 pipe_release+0x48/0x320 fs/pipe.c:727 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 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: 0033:0x7ff7bd37dff9 RSP: 002b:00007ffdd2e88bf8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ff7bd537a80 RCX: 00007ff7bd37dff9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ff7bd537a80 R08: 0000000000000006 R09: 00007ffdd2e88eef R10: 00000000003ffbc0 R11: 0000000000000246 R12: 0000000000021ff8 R13: 00007ffdd2e88d00 R14: 0000000000000226 R15: ffffffffffffffff INFO: task syz.0.636:7973 blocked for more than 141 seconds. Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.636 state:D stack:27392 pid:7973 tgid:7964 ppid:5230 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 pipe_write+0x1c6/0x1a30 fs/pipe.c:455 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff7bd37dff9 RSP: 002b:00007ff7be181038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ff7bd536130 RCX: 00007ff7bd37dff9 RDX: 0000000000000001 RSI: 0000000020003300 RDI: 0000000000000008 RBP: 00007ff7bd3f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007ff7bd536130 R15: 00007ffdd2e88a98 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by dhcpcd/4900: 2 locks held by getty/4984: #0: ffff88814bf140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.0.636/7964: #0: ffff888026b45868 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x48/0x320 fs/pipe.c:727 1 lock held by syz.0.636/7965: #0: ffff888026b45868 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 1 lock held by syz.0.636/7973: #0: ffff888026b45868 (&pipe->mutex){+.+.}-{3:3}, at: pipe_write+0x1c6/0x1a30 fs/pipe.c:455 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 101 PID: 5042 Comm: dhcpcd Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_acquire+0x6d/0x2050 kernel/locking/lockdep.c:5065 Code: c0 0f 85 9b 16 00 00 45 31 f6 83 3d f8 e6 ac 0e 00 0f 84 b6 13 00 00 89 54 24 54 89 5c 24 68 4c 89 f8 48 c1 e8 03 80 3c 30 00 <74> 12 4c 89 ff e8 a9 3a 8e 00 48 be 00 00 00 00 00 fc ff df 49 8b RSP: 0018:ffffc90002f2f8f0 EFLAGS: 00000046 RAX: 1ffff1100501f12b RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff8880280f8958 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff203a236 R12: ffff88801c3e9e00 R13: 0000000000000001 R14: 0000000000000000 R15: ffff8880280f8958 FS: 00007f6b963b2740(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200007c0 CR3: 000000007c84c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 __lock_task_sighand+0x149/0x2d0 kernel/signal.c:1410 lock_task_sighand include/linux/sched/signal.h:745 [inline] do_send_sig_info kernel/signal.c:1298 [inline] group_send_sig_info+0x274/0x310 kernel/signal.c:1449 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:857 ____bpf_send_signal kernel/trace/bpf_trace.c:862 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:860 bpf_prog_7ba5217f62dcd359+0x41/0x45 bpf_dispatcher_nop_func include/linux/bpf.h:1257 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2318 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2359 trace_sys_enter+0x93/0xd0 include/trace/events/syscalls.h:18 syscall_trace_enter+0xf8/0x150 kernel/entry/common.c:61 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline] syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline] do_syscall_64+0xcc/0x230 arch/x86/entry/common.c:79 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6b963ecad9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 <48> 81 ec b8 00 00 00 41 89 f9 48 89 f0 49 89 d0 48 85 f6 0f 84 be RSP: 002b:00007ffc17ec0b80 EFLAGS: 00000293 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 000055b1d06c0e20 RCX: 00007f6b963ecad9 RDX: 000055b1c9505610 RSI: 00007ffc17ec0cb0 RDI: 0000000000000011 RBP: 00007ffc17ec1480 R08: 0000000000000008 R09: 0000000000000000 R10: 00007ffc17ec1480 R11: 0000000000000293 R12: 0000000000000000 R13: 000055b1c9505610 R14: 00000000ffffffff R15: 0000000000000000