INFO: task kworker/u8:7:3446 blocked for more than 142 seconds. Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:7 state:D stack:22336 pid:3446 tgid:3446 ppid:2 flags:0x00004000 Workqueue: events_unbound flush_to_ldisc Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 ___down_common+0x2d7/0x460 kernel/locking/semaphore.c:225 __down_common kernel/locking/semaphore.c:246 [inline] __down+0x20/0x30 kernel/locking/semaphore.c:254 down+0x74/0xa0 kernel/locking/semaphore.c:63 console_lock+0x5b/0xa0 kernel/printk/printk.c:2833 do_con_write+0x154/0x7bb0 drivers/tty/vt/vt.c:3056 con_put_char+0x74/0xa0 drivers/tty/vt/vt.c:3442 tty_put_char+0xbc/0x160 drivers/tty/tty_io.c:3167 n_tty_process_echo_ops drivers/tty/n_tty.c:664 [inline] __process_echoes+0x80a/0xb40 drivers/tty/n_tty.c:709 process_echoes+0xf9/0x1c0 drivers/tty/n_tty.c:789 n_tty_receive_char_flow_ctrl drivers/tty/n_tty.c:1249 [inline] n_tty_receive_char_special drivers/tty/n_tty.c:1359 [inline] n_tty_receive_buf_standard+0x1070/0x3180 drivers/tty/n_tty.c:1604 __receive_buf drivers/tty/n_tty.c:1640 [inline] n_tty_receive_buf_common+0x8ed/0x1980 drivers/tty/n_tty.c:1739 tty_ldisc_receive_buf+0xa2/0x190 drivers/tty/tty_buffer.c:387 tty_port_default_receive_buf+0x70/0xb0 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x264/0x780 drivers/tty/tty_buffer.c:495 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task kworker/1:5:15960 blocked for more than 142 seconds. Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:5 state:D stack:23472 pid:15960 tgid:15960 ppid:2 flags:0x00004000 Workqueue: events vc_SAK Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x62b/0xa60 kernel/locking/mutex.c:735 tty_buffer_flush+0x72/0x310 drivers/tty/tty_buffer.c:229 tty_ldisc_flush+0x64/0xe0 drivers/tty/tty_ldisc.c:388 __do_SAK+0x6a1/0x800 drivers/tty/tty_io.c:3038 vc_SAK+0x7f/0x310 drivers/tty/vt/vt_ioctl.c:993 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.3.3793:20657 blocked for more than 142 seconds. Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.3793 state:D stack:25424 pid:20657 tgid:20657 ppid:16884 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 down_write_failed drivers/tty/tty_ldsem.c:262 [inline] __ldsem_down_write_nested+0x378/0x8d0 drivers/tty/tty_ldsem.c:324 __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline] tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:352 [inline] tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] tty_ldisc_release+0x159/0x2a0 drivers/tty/tty_ldisc.c:780 tty_release_struct+0x23/0xe0 drivers/tty/tty_io.c:1690 tty_release+0xe25/0x1410 drivers/tty/tty_io.c:1861 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xad8/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 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:329 [inline] irqentry_exit_to_user_mode+0x13f/0x280 kernel/entry/common.c:231 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f18e0b85d31 RSP: 002b:00000000fffffe10 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f18e0d75fa0 RCX: 00007f18e0b85d29 RDX: 0000000000000000 RSI: 00000000fffffe10 RDI: 0000000000000000 RBP: 00007f18e0c01b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f18e0d75fa0 R15: 00007ffe1da67288 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: 22547 Comm: syz.8.4201 Not tainted 6.13.0-rc7-syzkaller-00039-gc3812b15000c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0033:0x7ff0cd85f4b4 Code: 0f 82 b9 00 00 00 48 39 f2 72 6e 41 0f 11 0c 24 48 8b 77 f8 48 89 f8 48 89 eb eb 12 66 2e 0f 1f 84 00 00 00 00 00 48 8b 4b 08 <48> 83 c3 08 48 39 d1 72 f3 48 83 e8 08 48 39 f2 73 17 66 2e 0f 1f RSP: 002b:00007ffee4983bf0 EFLAGS: 00000297 RAX: 00007ff0cd1f7be8 RBX: 00007ff0cd1e7690 RCX: ffffffff81e17309 RDX: ffffffff81d9ccca RSI: ffffffff81e49c79 RDI: 00007ff0cd2dc4f0 RBP: 00007ff0cd14c270 R08: 00007ff0cd2143a8 R09: 00007ff0cdb62000 R10: 00007ff0ccfff008 R11: 0000000000000005 R12: 00007ff0cd14c268 R13: 0000000000000020 R14: 0000000000000032 R15: 00007ff0ccfff008 FS: 000055558f4c5500 GS: 0000000000000000