INFO: task syz.0.4028:17885 blocked for more than 143 seconds. Not tainted 6.11.0-rc6-syzkaller-00070-gc763c4339688 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.4028 state:D stack:23680 pid:17885 tgid:17885 ppid:16347 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 pipe_release+0x4e/0x330 fs/pipe.c:727 __fput+0x24a/0x8a0 fs/file_table.c:422 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: 0033:0x7f539c17cef9 RSP: 002b:00007ffef6fd0fc8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f539c337a80 RCX: 00007f539c17cef9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f539c337a80 R08: 0000000000000006 R09: 00007ffef6fd12bf R10: 00000000005f9878 R11: 0000000000000246 R12: 00000000000fafd9 R13: 00007ffef6fd10d0 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:7/2893: 1 lock held by udevd/4675: 2 locks held by getty/4980: #0: ffff8880359b00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.0.4028/17885: #0: ffff888032b4fc68 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x4e/0x330 fs/pipe.c:727 1 lock held by syz.0.4028/17892: #0: ffff888032b4fc68 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 1 lock held by udevd/17910: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc6-syzkaller-00070-gc763c4339688 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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: 17909 Comm: udevd Not tainted 6.11.0-rc6-syzkaller-00070-gc763c4339688 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:memset_orig+0x36/0xb0 arch/x86/lib/memset_64.S:68 Code: b8 01 01 01 01 01 01 01 01 48 0f af c1 41 89 f9 41 83 e1 07 75 70 48 89 d1 48 c1 e9 06 74 35 0f 1f 44 00 00 48 ff c9 48 89 07 <48> 89 47 08 48 89 47 10 48 89 47 18 48 89 47 20 48 89 47 28 48 89 RSP: 0018:ffffc9000916f9f8 EFLAGS: 00000002 RAX: fcfcfcfcfcfcfcfc RBX: 0000000000000024 RCX: 0000000000000007 RDX: 0000000000000200 RSI: 00000000000000fc RDI: ffffed1013a4a600 RBP: 0000000000000006 R08: dffffc0000000000 R09: 0000000000000000 R10: ffffed1013a4a600 R11: fffffbfff1fee86e R12: ffff88813fffa000 R13: 0000000000000000 R14: ffffea00027494c0 R15: ffff88801c2e5500 FS: 00007ff29aa90c80(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555a9fe42680 CR3: 0000000065aaa000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_poison_slab include/linux/kasan.h:130 [inline] allocate_slab+0x122/0x2f0 mm/slub.c:2510 new_slab mm/slub.c:2541 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3727 __slab_alloc+0x58/0xa0 mm/slub.c:3817 __slab_alloc_node mm/slub.c:3870 [inline] slab_alloc_node mm/slub.c:4029 [inline] kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4048 __sigqueue_alloc+0x42e/0x540 kernel/signal.c:428 __send_signal_locked+0x22f/0xdc0 kernel/signal.c:1119 do_send_sig_info kernel/signal.c:1301 [inline] group_send_sig_info+0x292/0x310 kernel/signal.c:1451 bpf_send_signal_common+0x2dd/0x430 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x19/0x30 kernel/trace/bpf_trace.c:884 bpf_prog_7ba5217f62dcd359+0x40/0x44 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2447 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: 0033:0x7ff29a723457 Code: 73 01 c3 48 8b 0d d1 d9 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 e8 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 76 48 8b 15 a2 d9 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffd5a6b9c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff29a723457 RDX: 0000000000000004 RSI: 00007ffd5a6b9c58 RDI: 0000000000000004 RBP: 00007ffd5a6b9c64 R08: 0000000000000007 R09: e4b08aa94019d87f R10: 00000000ffffffff R11: 0000000000000246 R12: 0000556632cd5d90 R13: 00007ffd5a6b9c58 R14: 0000000000000001 R15: 0000556632cb7910