INFO: task syz.4.1238:10433 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00042-g1a1d569a75f3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1238 state:D stack:24200 pid:10433 tgid:10433 ppid:9936 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_timeout+0xb1/0x2b0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x32f/0x600 kernel/sched/completion.c:148 __flush_work+0xa48/0xc60 kernel/workqueue.c:4244 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4364 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_release+0xac/0x600 drivers/hid/uhid.c:662 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 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:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc19038e169 RSP: 002b:00007fc1906dfb88 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fc1905b7ba0 RCX: 00007fc19038e169 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fc1905b7ba0 R08: 0000000000000000 R09: 0000001e906dfe7f R10: 00007fc1905b7ac0 R11: 0000000000000246 R12: 00000000000714ee R13: 00007fc1905b6080 R14: ffffffffffffffff R15: 00007fc1906dfca0 Showing all locks held in the system: 2 locks held by kworker/u8:0/12: #0: ffff88801eab5148 ( (wq_completion)iou_exit){+.+.}-{0:0}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:613 #1: ffff8880b8723b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41f/0x7a0 kernel/sched/psi.c:987 1 lock held by khungtaskd/31: #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3dfa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 6 locks held by kworker/0:2/975: #0: ffff888144683548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888144683548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003907c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003907c60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff888145b02198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #2: ffff888145b02198 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5859 #3: ffff888032c85198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #3: ffff888032c85198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x103/0x960 drivers/usb/core/hub.c:2307 #4: ffff88807ea38160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] ffff88807ea38160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] ffff88807ea38160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffffffff8fb83808 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:201 [inline] ffffffff8fb83808 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2ff/0x630 drivers/input/input.c:2221 2 locks held by getty/5594: #0: ffff8880359220a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5856: #0: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 3 locks held by kworker/0:3/5895: 2 locks held by syz.3.1619/11799: #0: ffff888078448e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888078448e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff888078448e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1391 #1: ffff88807d032258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline] #1: ffff88807d032258 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1eb/0x950 net/can/bcm.c:1571 3 locks held by syz.1.1622/11813: #0: ffff88802a3da160 (&mousedev->mutex #2){+.+.}-{4:4}, at: mousedev_close_device+0x2e/0xe0 drivers/input/mousedev.c:441 #1: ffff88802a3d92c0 (&dev->mutex#2 ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:201 [inline] , at: input_close_device+0x4b/0x260 drivers/input/input.c:645 #2: ffffffff8ed434b8 (rcu_state.exp_mutex){+.+.}-{4:4} , at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] , at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 2 locks held by syz.1.1622/11815: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00042-g1a1d569a75f3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5895 Comm: kworker/0:3 Not tainted 6.15.0-rc2-syzkaller-00042-g1a1d569a75f3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events uhid_device_add_worker RIP: 0010:serial8250_console_write+0x1229/0x1e00 drivers/tty/serial/8250/8250_port.c:3446 Code: c0 20 d0 68 93 65 48 8b 00 48 3b 84 24 80 01 00 00 0f 85 e2 0b 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc <49> 8d 9f 08 01 00 00 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 RSP: 0018:ffffc900041bebe0 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000081 RCX: ffff888030eb9e00 RDX: ffff888030eb9e00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900041bedb0 R08: ffffffff859755dc R09: fffff52000837d58 R10: dffffc0000000000 R11: ffffffff85978a50 R12: ffffffff9aa84df0 R13: dffffc0000000000 R14: 1ffffffff35509be R15: ffffffff9aa84b40 FS: 0000000000000000(0000) GS:ffff888124f93000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb9d097fab8 CR3: 0000000033b36000 CR4: 00000000003526f0 DR0: 0000000000000680 DR1: 0000000000000003 DR2: 0000000000000007 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x86b/0xec0 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325 vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450 dev_vprintk_emit+0x358/0x420 drivers/base/core.c:4891 dev_printk_emit+0xdf/0x130 drivers/base/core.c:4902 _dev_warn+0x12d/0x180 drivers/base/core.c:4958 hid_parser_main+0x896/0xc40 drivers/hid/hid-core.c:-1 hid_open_report+0xbda/0x1590 drivers/hid/hid-core.c:1328 hid_parse include/linux/hid.h:1126 [inline] hid_generic_probe+0x3d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2717 [inline] hid_device_probe+0x3bf/0x710 drivers/hid/hid-core.c:2754 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x258/0x2e0 drivers/base/bus.c:462 __device_attach+0x341/0x530 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3666 hid_add_device+0x3b6/0x520 drivers/hid/hid-core.c:2900 uhid_device_add_worker+0x44/0xf0 drivers/hid/uhid.c:73 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245