INFO: task syz.3.4:3743 blocked for more than 143 seconds. Not tainted 6.1.106-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.4 state:D stack:25832 pid:3743 ppid:3653 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 __pipe_lock fs/pipe.c:103 [inline] pipe_release+0x4d/0x320 fs/pipe.c:724 __fput+0x3f6/0x8d0 fs/file_table.c:320 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 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+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd923b79ef9 RSP: 002b:00007ffe23e22ff8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fd923d17a80 RCX: 00007fd923b79ef9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fd923d17a80 R08: 0000000000000006 R09: 00007ffe23e232ef R10: 00000000005fc058 R11: 0000000000000246 R12: 0000000000010cc1 R13: 00007ffe23e23100 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b190 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 2 locks held by udevd/3092: 2 locks held by getty/3397: #0: ffff8880289d0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 1 lock held by syz.3.4/3743: #0: ffff88807468cc68 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] #0: ffff88807468cc68 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_release+0x4d/0x320 fs/pipe.c:724 1 lock held by syz.3.4/3744: #0: ffff88807468cc68 (&pipe->mutex/1){+.+.}-{3:3}, at: splice_file_to_pipe+0x2a/0x3d0 fs/splice.c:1038 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 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+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3306 Comm: dhcpcd Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:unwind_next_frame+0x6f3/0x2220 arch/x86/kernel/unwind_orc.c:475 Code: 00 74 0e 49 89 fe 48 89 df e8 79 73 a5 00 4c 89 f7 48 8b 1b 48 85 db 0f 84 1c 0b 00 00 48 83 c3 70 e9 e8 01 00 00 4c 8b 24 24 <49> 8d 5c 24 40 48 89 d8 48 c1 e8 03 80 3c 38 00 74 0e 49 89 fe 48 RSP: 0018:ffffc9000354f4a0 EFLAGS: 00000093 RAX: 0000000000000002 RBX: 0000000000000004 RCX: ffffffff8ea80420 RDX: ffffffff8f138bf8 RSI: ffffffff812fd0f0 RDI: dffffc0000000000 RBP: ffffffff8f138c1c R08: 0000000000000007 R09: ffffc9000354f670 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000354f580 R13: ffffffff8f138c20 R14: ffffffff8ea80404 R15: 1ffffffff1e27184 FS: 00007f39dfb0a740(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0023715f88 CR3: 000000001f4e8000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x292/0x510 mm/slub.c:3683 __sigqueue_free kernel/signal.c:458 [inline] collect_signal kernel/signal.c:601 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:623 dequeue_signal+0x165/0x590 kernel/signal.c:646 get_signal+0x5f2/0x17d0 kernel/signal.c:2750 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 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+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f39dfbd7ad5 Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffd2a839020 EFLAGS: 00000246 ORIG_RAX: 000000000000010f RAX: fffffffffffffdfe RBX: 000055ffaa54fe20 RCX: 00007f39dfbd7ad5 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 000055ffaa54fe00 RBP: 00007ffd2a839370 R08: 0000000000000008 R09: 8131740a1c403202 R10: 00007ffd2a839370 R11: 0000000000000246 R12: 0000000000000000 R13: 000055ffa95a2610 R14: 00000000ffffffff R15: 0000000000000000