INFO: task syz.7.279:6537 blocked for more than 147 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.7.279 state:D stack:23808 pid:6537 tgid:6537 ppid:6239 flags:0x00004002 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: 0033:0x7f2e25d7e719 RSP: 002b:00007ffd560b52f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2e25f37a80 RCX: 00007f2e25d7e719 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2e25f37a80 R08: 0000000000000006 R09: 00007ffd560b55ef R10: 00000000003ffbb0 R11: 0000000000000246 R12: 0000000000030d16 R13: 00007ffd560b5400 R14: 0000000000000032 R15: ffffffffffffffff INFO: task syz.7.279:6542 blocked for more than 149 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.7.279 state:D stack:27392 pid:6542 tgid:6537 ppid:6239 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: 0033:0x7f2e25d7e719 RSP: 002b:00007f2e257ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2e25f36130 RCX: 00007f2e25d7e719 RDX: 0000000000000001 RSI: 0000000020003300 RDI: 000000000000000a RBP: 00007f2e25df132e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f2e25f36130 R15: 00007ffd560b5198 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 udevd/4687: 2 locks held by getty/4987: #0: ffff8880326320a0 (&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 dhcpcd/6427: 1 lock held by syz.7.279/6537: #0: ffff88807d8bcc68 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x48/0x320 fs/pipe.c:727 1 lock held by syz.7.279/6540: #0: ffff88807d8bcc68 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 1 lock held by syz.7.279/6542: #0: ffff88807d8bcc68 (&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: 4903 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:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d 04 3b 9d 0c 48 89 de 5b e9 c3 c7 5d 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 00 d8 03 00 65 8b 15 a0 f0 6e 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc90002eefd60 EFLAGS: 00000282 RAX: ffffffff81369cea RBX: ffff88802d9f9940 RCX: ffff88802d9f8000 RDX: 0000000000000000 RSI: ffffffff8c059c40 RDI: ffffffff8c60fb20 RBP: dffffc0000000000 R08: ffffffff81371544 R09: 1ffffffff203a235 R10: dffffc0000000000 R11: fffffbfff203a236 R12: ffff88802d9f8000 R13: ffffffff813690bc R14: ffff88802d9f9940 R15: ffff88802d9f9940 FS: 00007fa0a64a9740(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020e5c000 CR3: 000000002d3cc000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] static_key_false include/linux/jump_label.h:207 [inline] trace_x86_fpu_regs_activated arch/x86/include/asm/trace/fpu.h:57 [inline] fpregs_activate+0x2a/0x200 arch/x86/kernel/fpu/context.h:50 fpregs_mark_activate arch/x86/kernel/fpu/core.c:831 [inline] fpu__clear_user_states+0x17d/0x270 arch/x86/kernel/fpu/core.c:770 handle_signal arch/x86/kernel/signal.c:310 [inline] arch_do_signal_or_restart+0x4fb/0x860 arch/x86/kernel/signal.c:339 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: 0033:0x55bff66caf1a Code: ff 80 bd a0 01 00 00 03 74 bc 48 8d 3d 74 a3 02 00 31 c0 e8 d0 12 00 00 eb ac 48 81 c4 a0 00 00 00 5b 5d 41 5c 41 5d 41 5e c3 <48> 8b 05 df 06 04 00 48 83 f8 05 74 1c 48 8b 05 d2 06 04 00 48 8d RSP: 002b:00007fff8cce8b78 EFLAGS: 00000246 ORIG_RAX: 000000000000010f RAX: 0000000000000000 RBX: 000055c016b31e20 RCX: 00007fa0a6576ad5 RDX: 00007fff8cce8b80 RSI: 00007fff8cce8cb0 RDI: 0000000000000011 RBP: 00007fff8cce9490 R08: 0000000000000008 R09: 000055bff670b3d0 R10: 00007fff8cce9490 R11: 0000000000000246 R12: 0000000000000000 R13: 000055bff670b610 R14: 00000000ffffffff R15: 0000000000000000