INFO: task syz-executor.2:19243 blocked for more than 143 seconds. Not tainted 6.1.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27120 pid:19243 ppid:3654 flags:0x00024000 Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0xae9/0x53f0 kernel/sched/core.c:6503 schedule+0xda/0x1b0 kernel/sched/core.c:6579 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1911 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x1ca/0x5c0 kernel/sched/completion.c:106 io_wq_exit_workers io_uring/io-wq.c:1253 [inline] io_wq_put_and_exit+0x243/0xe20 io_uring/io-wq.c:1288 io_uring_clean_tctx+0x113/0x174 io_uring/tctx.c:193 io_uring_cancel_generic+0x5aa/0x602 io_uring/io_uring.c:3014 io_uring_files_cancel include/linux/io_uring.h:51 [inline] do_exit+0x533/0x2a20 kernel/exit.c:775 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 get_signal+0x21a1/0x2430 kernel/signal.c:2858 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:296 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6c7848b5a9 RSP: 002b:00007f6c792a9168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007f6c785ac050 RCX: 00007f6c7848b5a9 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000089 RBP: 00007f6c784e67b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6c786cfb1f R14: 00007f6c792a9300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8bf87f70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8bf87c70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8bf88ac0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6494 2 locks held by getty/3286: #0: ffff88814af9d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef0/0x13e0 drivers/tty/n_tty.c:2177 3 locks held by iou-wrk-19243/19254: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x32f/0x3c0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xc71/0xfc0 kernel/hung_task.c:377 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 19254 Comm: iou-wrk-19243 Not tainted 6.1.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:io_serial_out+0x8b/0xa0 drivers/tty/serial/8250/8250_port.c:467 Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 18 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 e8 a9 52 65 fd eb a4 e8 d2 52 65 fd eb e1 41 RSP: 0018:ffffc9000562f3b0 EFLAGS: 00000002 RAX: 0000000000000031 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff8463acf1 RDI: ffffffff914cf200 RBP: ffffffff914cf1c0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000031 R14: ffffffff8463ac90 R15: 0000000000000000 FS: 00007f6c792a9700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc865d82058 CR3: 000000007d43a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:123 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3362 [inline] serial8250_console_write+0xd0e/0x1010 drivers/tty/serial/8250/8250_port.c:3433 call_console_driver kernel/printk/printk.c:1942 [inline] console_emit_next_record.constprop.0+0x3de/0x840 kernel/printk/printk.c:2731 console_flush_all kernel/printk/printk.c:2793 [inline] console_unlock+0x3be/0x600 kernel/printk/printk.c:2860 vprintk_emit+0x1b9/0x5f0 kernel/printk/printk.c:2268 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2289 device_read.cold+0x1d/0x172 fs/dlm/user.c:813 loop_rw_iter+0x1be/0x540 io_uring/rw.c:455 io_iter_do_read io_uring/rw.c:639 [inline] io_iter_do_read io_uring/rw.c:632 [inline] io_read+0x101b/0x1420 io_uring/rw.c:759 io_issue_sqe+0x153/0x1210 io_uring/io_uring.c:1738 io_wq_submit_work+0x299/0x14e0 io_uring/io_uring.c:1815 io_worker_handle_work+0x5f4/0x1590 io_uring/io-wq.c:587 io_wqe_worker+0x9e1/0xe30 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306