INFO: task udevd:4905 blocked for more than 143 seconds. Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24448 pid:4905 tgid:4905 ppid:2547 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 device_lock include/linux/device.h:1009 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2743 dev_attr_show+0x53/0xe0 drivers/base/core.c:2437 sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59 seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230 kernfs_fop_read_iter+0x41a/0x590 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:395 [inline] vfs_read+0x869/0xbd0 fs/read_write.c:476 ksys_read+0x12f/0x260 fs/read_write.c:619 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: 0033:0x7f25c9406b6a RSP: 002b:00007fff7bcf9428 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005596b685d880 RCX: 00007f25c9406b6a RDX: 0000000000001000 RSI: 00005596b6895fb0 RDI: 0000000000000001 RBP: 00005596b685d880 R08: 0000000000000001 R09: 0000000000002000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff7bcf9908 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff88cb68a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6620 2 locks held by getty/2605: #0: ffff888113b610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 4 locks held by udevd/4905: #0: ffff8881168168b8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xde/0x12c0 fs/seq_file.c:182 #1: ffff88811534e888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88811f5bc1e8 (kn->active#3){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888115855190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff888115855190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2743 6 locks held by kworker/0:3/4923: 6 locks held by kworker/1:5/4987: 6 locks held by kworker/1:0/8665: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 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+0xf4e/0x1280 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 4923 Comm: kworker/0:3 Not tainted 6.11.0-rc1-syzkaller-00033-g25f51b76f90f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: usb_hub_wq hub_event RIP: 0010:__sanitizer_cov_trace_pc+0x38/0x60 kernel/kcov.c:210 Code: 05 e5 5f b0 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 35 8b 82 54 15 00 00 85 c0 74 2b 8b 82 30 15 00 00 83 f8 02 75 20 <48> 8b 8a 38 15 00 00 8b 92 34 15 00 00 48 8b 01 48 83 c0 01 48 39 RSP: 0018:ffffc9000237ebb8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffc9000237ec88 RCX: ffffc9000ce82000 RDX: ffff88811bd78000 RSI: ffffffff81155c99 RDI: 0000000000000005 RBP: ffffc9000237fcc0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000237ec90 R13: ffffc9000237ec98 R14: 0000000000000001 R15: ffffc90002380000 FS: 0000000000000000(0000) GS:ffff8881f6200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe84111ff8 CR3: 000000012290e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: stack_access_ok+0xf9/0x270 arch/x86/kernel/unwind_orc.c:389 deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0xd9b/0x23a0 arch/x86/kernel/unwind_orc.c:585 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4158 [inline] __kmalloc_noprof+0x1e3/0x3c0 mm/slub.c:4170 kmalloc_noprof include/linux/slab.h:685 [inline] usb_alloc_urb+0x69/0xa0 drivers/usb/core/urb.c:75 try_queue_bulk_in+0x266/0x7f0 drivers/char/xillybus/xillyusb.c:729 xillyusb_setup_base_eps drivers/char/xillybus/xillyusb.c:1924 [inline] xillyusb_probe+0x47b/0x830 drivers/char/xillybus/xillyusb.c:2161 usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399 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:3679 usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294 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:3679 usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651 hub_port_connect drivers/usb/core/hub.c:5521 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x2e66/0x4f50 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 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