INFO: task kworker/u8:4:62 blocked for more than 144 seconds. Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:23184 pid:62 tgid:62 ppid:2 flags:0x00004000 Workqueue: events_unbound flush_to_ldisc Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5730 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591 ___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:2808 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 flush_echoes drivers/tty/n_tty.c:807 [inline] __receive_buf drivers/tty/n_tty.c:1642 [inline] n_tty_receive_buf_common+0xa2a/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:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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/0:4:5884 blocked for more than 144 seconds. Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:21392 pid:5884 tgid:5884 ppid:2 flags:0x00004000 Workqueue: events vc_SAK Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5730 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 tty_buffer_flush+0x72/0x310 drivers/tty/tty_buffer.c:229 tty_ldisc_flush+0xa4/0xe0 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:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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/0:6:9250 blocked for more than 144 seconds. Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:21712 pid:9250 tgid:9250 ppid:2 flags:0x00004000 Workqueue: events console_callback Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5730 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591 ___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:2808 console_callback+0x63/0x4c0 drivers/tty/vt/vt.c:3120 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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.0.805:9475 blocked for more than 144 seconds. Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.805 state:D stack:25392 pid:9475 tgid:9475 ppid:6538 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5730 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591 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+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 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+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d7dd7e719 RSP: 002b:00007fff14e1e6a8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f8d7df37a80 RCX: 00007f8d7dd7e719 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f8d7df37a80 R08: 00007f8d7df22000 R09: 00007fff14e1e99f R10: 00000000003ffc30 R11: 0000000000000246 R12: 0000000000046f10 R13: 00007fff14e1e7b0 R14: 0000000000000032 R15: ffffffffffffffff INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #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+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:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11984 Comm: syz.8.1203 Not tainted 6.12.0-rc5-syzkaller-00308-g3e5e6c9900c3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__put_user_4+0x18/0x20 arch/x86/lib/putuser.S:91 Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb 89 01 31 c9 0f 01 ca cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900053f7ca8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff88f11987 RDI: 0000000000000000 RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff20beb39 R10: ffffffff905f59cf R11: 0000000000000000 R12: 0000000000008b20 R13: 0000000000000000 R14: 000000002022c8c0 R15: 0000000000010106 FS: 00007fd20de146c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002022c030 CR3: 00000000acc36000 CR4: 00000000003526f0 DR0: 0000000000002800 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: do_recvmmsg+0x2f2/0x750 net/socket.c:2968 __sys_recvmmsg net/socket.c:3041 [inline] __do_sys_recvmmsg net/socket.c:3064 [inline] __se_sys_recvmmsg net/socket.c:3057 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3057 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd20cf7e719 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd20de14038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fd20d136058 RCX: 00007fd20cf7e719 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007fd20cff132e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fd20d136058 R15: 00007ffc62171288