INFO: task syz.1.1087:9929 blocked for more than 159 seconds. Not tainted 6.12.0-rc7-syzkaller-00135-g8ffade77b633 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1087 state:D stack:25920 pid:9929 tgid:9929 ppid:5840 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842 __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:239 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: 0033:0x7f7eae37e719 RSP: 002b:00007ffd99b7c4f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f7eae537a80 RCX: 00007f7eae37e719 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f7eae537a80 R08: 0000000000000006 R09: 00007ffd99b7c7ef R10: 00000000003ffc4c R11: 0000000000000246 R12: 000000000002d87f R13: 00007ffd99b7c600 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by getty/5599: #0: ffff8880313e40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.1.1087/9929: #0: ffff88805db22c68 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x48/0x320 fs/pipe.c:727 1 lock held by syz.1.1087/9933: #0: ffff88805db22c68 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 4 locks held by syz.3.1111/10012: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc7-syzkaller-00135-g8ffade77b633 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5830 Comm: syz-executor Not tainted 6.12.0-rc7-syzkaller-00135-g8ffade77b633 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:arch_stack_walk+0x123/0x150 arch/x86/kernel/stacktrace.c:24 Code: 63 9c 09 00 48 85 c0 74 23 4c 89 f7 48 89 c6 4d 89 eb 41 ff d3 66 90 84 c0 74 11 48 89 df e8 94 9d 09 00 83 bd 70 ff ff ff 00 <75> d0 65 48 8b 04 25 28 00 00 00 48 3b 45 d0 75 13 48 83 c4 68 5b RSP: 0018:ffffc9000373f700 EFLAGS: 00000002 RAX: 0000000080000001 RBX: ffffc9000373f700 RCX: 0000000080000001 RDX: dffffc0000000000 RSI: ffffc90003738000 RDI: 0000000000000001 RBP: ffffc9000373f790 R08: ffffc9000373fdb0 R09: 0000000000000000 R10: ffffc9000373f750 R11: fffff520006e7eec R12: ffff88807fd39e00 R13: ffffffff8180a270 R14: ffffc9000373f7e0 R15: 0000000000000000 FS: 000055555c6b0500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc6b6f1368 CR3: 000000002831e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x1a2/0x420 mm/slub.c:4681 __sigqueue_free kernel/signal.c:452 [inline] collect_signal kernel/signal.c:595 [inline] __dequeue_signal+0x4ac/0x5c0 kernel/signal.c:617 dequeue_signal+0x1e0/0x680 kernel/signal.c:638 get_signal+0x604/0x1740 kernel/signal.c:2798 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: 0033:0x7f398eb7e4dc Code: 29 44 24 30 80 3d 7b f0 18 00 00 4c 89 4c 24 40 4c 8d 4c 24 40 48 c7 44 24 48 08 00 00 00 74 2e 4c 89 ea b8 0e 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7c 48 8b 54 24 58 64 48 2b 14 25 28 00 00 00 RSP: 002b:00007ffe168885b0 EFLAGS: 00000202 RAX: fffffffffffffffc RBX: 00007ffe168886e0 RCX: 00007f398eb7e4dc RDX: 0000000000000000 RSI: 00007ffe168886e0 RDI: 0000000000000026 RBP: 00007ffe16888b30 R08: 00007ffe168885e0 R09: 00007ffe168885f0 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe16888980 R13: 0000000000000000 R14: 00007ffe16888a00 R15: 00007ffe16888770