INFO: task syz.1.876:7980 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.876 state:D stack:28160 pid:7980 tgid:7939 ppid:6252 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2557 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3de/0x5f0 kernel/sched/completion.c:116 __flush_work+0x776/0xc30 kernel/workqueue.c:4212 __cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4332 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_write+0xc0b/0x10c0 drivers/hid/uhid.c:761 vfs_write+0x29a/0x1140 fs/read_write.c:588 ksys_write+0x1f8/0x260 fs/read_write.c:643 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: 0033:0x7fb00cf79eb9 RSP: 002b:00007fb00dd33038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb00d116058 RCX: 00007fb00cf79eb9 RDX: 0000000000000004 RSI: 00000000200011c0 RDI: 0000000000000003 RBP: 00007fb00cfe793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fb00d116058 R15: 00007ffe22c072e8 Showing all locks held in the system: 7 locks held by kworker/1:0/25: 2 locks held by kworker/u8:2/29: 1 lock held by khungtaskd/31: #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 1 lock held by syslogd/4662: 2 locks held by getty/4987: #0: ffff8880309fc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:6/5313: 1 lock held by syz.1.876/7980: #0: ffff88805e100068 (&uhid->devlock){+.+.}-{3:3}, at: uhid_char_write+0x71/0x10c0 drivers/hid/uhid.c:731 2 locks held by syz.3.1528/9797: 2 locks held by syz.0.1530/9800: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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: 25 Comm: kworker/1:0 Not tainted 6.11.0-rc5-syzkaller-00310-ge8784b0aef62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events uhid_device_add_worker RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:413 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 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 31 a0 e7 fc eb a0 e8 ba a0 e7 RSP: 0018:ffffc900001f7160 EFLAGS: 00000002 RAX: 000000000000002e RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff8502e1a5 RDI: ffffffff9a5b2f20 RBP: ffffffff9a5b2ee0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 000000000000002e R14: ffffffff8502e140 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffeef3f477c CR3: 000000003129a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:142 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline] serial8250_console_write+0xce7/0x1090 drivers/tty/serial/8250/8250_port.c:3393 console_emit_next_record kernel/printk/printk.c:2983 [inline] console_flush_all+0x53c/0xd70 kernel/printk/printk.c:3049 console_unlock+0xae/0x290 kernel/printk/printk.c:3118 vprintk_emit+0x409/0x600 kernel/printk/printk.c:2348 dev_vprintk_emit drivers/base/core.c:4912 [inline] dev_printk_emit+0xfb/0x140 drivers/base/core.c:4923 __dev_printk+0xf5/0x270 drivers/base/core.c:4935 _dev_warn+0xe5/0x120 drivers/base/core.c:4979 hid_parser_main+0x2b6/0xc70 drivers/hid/hid-core.c:632 hid_open_report+0x3f4/0x7c0 drivers/hid/hid-core.c:1276 hid_parse include/linux/hid.h:1118 [inline] hid_generic_probe+0x4d/0x90 drivers/hid/hid-generic.c:63 __hid_device_probe drivers/hid/hid-core.c:2674 [inline] hid_device_probe+0x2eb/0x490 drivers/hid/hid-core.c:2711 call_driver_probe drivers/base/dd.c:578 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:657 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:957 bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:457 __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1029 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:532 device_add+0x114b/0x1a70 drivers/base/core.c:3682 hid_add_device+0x37f/0xa70 drivers/hid/hid-core.c:2857 uhid_device_add_worker+0x3e/0x110 drivers/hid/uhid.c:73 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 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