INFO: task syz.3.1503:12917 blocked for more than 143 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.3.1503 state:D stack:23808 pid:12917 tgid:12917 ppid:12735 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: 0033:0x7f2d0fb7dff9 RSP: 002b:00007ffcaa302448 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2d0fd37a80 RCX: 00007f2d0fb7dff9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2d0fd37a80 R08: 0000000000000006 R09: 00007ffcaa30273f R10: 00000000005f6a18 R11: 0000000000000246 R12: 00000000000a171b R13: 00007ffcaa302550 R14: 0000000000000032 R15: ffffffffffffffff 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 getty/4991: #0: ffff88802ebff0a0 (&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 sshd/5219: 1 lock held by syz-executor/12833: 1 lock held by syz.3.1503/12917: #0: ffff88807e781868 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x48/0x320 fs/pipe.c:727 1 lock held by syz.3.1503/12918: #0: ffff88807e781868 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 ============================================= 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: 0 PID: 5219 Comm: sshd 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:lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] RIP: 0010:lock_release+0x5f9/0xa30 kernel/locking/lockdep.c:5848 Code: 10 48 8b 5c 24 28 49 89 dd 4c 8d b4 24 90 00 00 00 48 c7 c7 40 dc 0a 8c e8 44 83 56 0a b8 ff ff ff ff 65 0f c1 05 77 07 92 7e <83> f8 01 0f 85 9a 00 00 00 4c 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 RSP: 0018:ffffc90002e8fb20 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000046 RCX: ffffc90002e8fb03 RDX: 0000000000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c60fb20 RBP: ffffc90002e8fc60 R08: ffffffff901d11af R09: 1ffffffff203a235 R10: dffffc0000000000 R11: fffffbfff203a236 R12: 1ffff920005d1f70 R13: 0000000000000046 R14: ffffc90002e8fbb0 R15: dffffc0000000000 FS: 00007f8e1bb08800(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa51094a040 CR3: 0000000077e90000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:157 [inline] _raw_spin_unlock_irq+0x16/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x14df/0x1740 kernel/signal.c:2920 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8e1b6c2773 Code: 00 f3 a5 48 8d 74 24 88 48 b9 ff ff ff 7f fe ff ff ff 48 21 c8 48 89 44 24 88 41 ba 08 00 00 00 44 89 c7 b8 0e 00 00 00 0f 05 <45> 31 c0 3d 00 f0 ff ff 76 06 41 89 c0 41 f7 d8 44 89 c0 5a c3 41 RSP: 002b:00007fffffd30b70 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000060001 RCX: 00007f8e1b6c2773 RDX: 00007fffffd30c58 RSI: 00007fffffd30bd8 RDI: 0000000000000001 RBP: 00005616d8c63240 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 00005616cfaf9aa4 R13: 00000000000002c3 R14: 00005616cfafa3e8 R15: 00007fffffd30bd8