INFO: task udevd:5877 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:20168 pid:5877 tgid:5877 ppid:5195 task_flags:0x400140 flags:0x00080802 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 io_schedule+0x80/0xd0 kernel/sched/core.c:7801 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 folio_put_wait_locked mm/filemap.c:1487 [inline] do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4077 read_mapping_folio include/linux/pagemap.h:1017 [inline] read_part_sector+0xb6/0x2b0 block/partitions/core.c:722 adfspart_check_POWERTEC+0x8c/0xf30 block/partitions/acorn.c:454 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x75f/0x14b0 block/partitions/core.c:693 blkdev_get_whole+0x380/0x510 block/bdev.c:748 bdev_open+0x31e/0xd30 block/bdev.c:957 blkdev_open+0x457/0x600 block/fops.c:702 do_dentry_open+0x953/0x13f0 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3975 [inline] path_openat+0x2efb/0x3860 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 do_sys_openat2+0x121/0x1c0 fs/open.c:1434 do_sys_open fs/open.c:1449 [inline] __do_sys_openat fs/open.c:1465 [inline] __se_sys_openat fs/open.c:1460 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1460 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa9e64a7407 RSP: 002b:00007ffc1f022c70 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa9e6ca1880 RCX: 00007fa9e64a7407 RDX: 00000000000a0800 RSI: 000055bd100e8290 RDI: ffffffffffffff9c RBP: 000055bd100c6910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055bd1013f9a0 R13: 000055bd100d4190 R14: 0000000000000000 R15: 000055bd1013f9a0 INFO: task udevd:6068 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:20584 pid:6068 tgid:6068 ppid:5195 task_flags:0x400140 flags:0x00080803 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 io_schedule+0x80/0xd0 kernel/sched/core.c:7801 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 folio_put_wait_locked mm/filemap.c:1487 [inline] do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4077 read_mapping_folio include/linux/pagemap.h:1017 [inline] read_part_sector+0xb6/0x2b0 block/partitions/core.c:722 adfspart_check_POWERTEC+0x8c/0xf30 block/partitions/acorn.c:454 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x75f/0x14b0 block/partitions/core.c:693 blkdev_get_whole+0x380/0x510 block/bdev.c:748 bdev_open+0x31e/0xd30 block/bdev.c:957 blkdev_open+0x457/0x600 block/fops.c:702 do_dentry_open+0x953/0x13f0 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3975 [inline] path_openat+0x2efb/0x3860 fs/namei.c:4134 do_filp_open+0x1fa/0x410 fs/namei.c:4161 do_sys_openat2+0x121/0x1c0 fs/open.c:1434 do_sys_open fs/open.c:1449 [inline] __do_sys_openat fs/open.c:1465 [inline] __se_sys_openat fs/open.c:1460 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1460 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa9e64a7407 RSP: 002b:00007ffc1f022c70 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa9e6ca1880 RCX: 00007fa9e64a7407 RDX: 00000000000a0800 RSI: 000055bd100de760 RDI: ffffffffffffff9c RBP: 000055bd100c6910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055bd100f30f0 R13: 000055bd100d4190 R14: 0000000000000000 R15: 000055bd100f30f0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5578: #0: ffff88802f7570a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5877: #0: ffff888142b03358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 5 locks held by kworker/0:5/5938: #0: ffff888142eb4d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242 #1: ffffc9000490fb80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243 #2: ffff888144708198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888144708198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff888057b65198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #3: ffff888057b65198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 #4: ffff8880701b0160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #4: ffff8880701b0160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 1 lock held by udevd/6068: #0: ffff888142351358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945 4 locks held by udevd/9898: #0: ffff88807ecb6c30 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20 fs/seq_file.c:182 #1: ffff88806c5ac088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172 #2: ffff888056469e18 (kn->active#19){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888056469e18 (kn->active#19){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173 #3: ffff888057b65198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline] #3: ffff888057b65198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:336 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:499 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 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: 5938 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:80 [inline] RIP: 0010:rcu_is_watching+0x9/0xb0 kernel/rcu/tree.c:750 Code: 22 03 eb cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 <65> ff 05 f0 76 ce 10 e8 9b e4 b4 09 89 c3 83 f8 08 73 65 49 bf 00 RSP: 0018:ffffc90000007c70 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8191b878 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f7da970 RBP: ffff88802b2e1e80 R08: ffffffff8f7da977 R09: 1ffffffff1efb52e R10: dffffc0000000000 R11: fffffbfff1efb52f R12: dffffc0000000000 R13: 1ffff1100565c3d3 R14: 0000000000000000 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff888125ec2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30907ff8 CR3: 00000000695f6000 CR4: 00000000003526f0 Call Trace: trace_sched_waking+0x37/0x110 include/trace/events/sched.h:170 try_to_wake_up+0xc1/0x12b0 kernel/sched/core.c:4114 hrtimer_wakeup+0x4e/0x60 kernel/time/hrtimer.c:2013 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2034 [inline] RIP: 0010:vprintk_emit+0x49d/0x590 kernel/printk/printk.c:2422 Code: 0f 84 34 ff ff ff e8 12 68 20 00 fb eb 44 e8 0a 68 20 00 e8 45 19 bb 09 4d 85 f6 74 94 e8 fb 67 20 00 fb 48 c7 c7 60 f8 f2 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 bb 27 RSP: 0018:ffffc9000490e5c0 EFLAGS: 00000283 RAX: ffffffff81a11835 RBX: ffffffff81a1168e RCX: 0000000000100000 RDX: ffffc90019cf7000 RSI: 000000000002d85d RDI: ffffffff8df2f860 RBP: ffffc9000490e6d0 R08: ffffffff8f7da977 R09: 1ffffffff1efb52e R10: dffffc0000000000 R11: fffffbfff1efb52f R12: 0000000000000000 R13: 000000000000006d R14: 0000000000000200 R15: 1ffff92000921cbc dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 __netdev_printk+0x3d7/0x4d0 net/core/dev.c:12911 netdev_warn+0x10a/0x160 net/core/dev.c:12964 lan78xx_read_reg+0x1d5/0x240 drivers/net/usb/lan78xx.c:619 lan78xx_read_raw_eeprom+0x45/0x530 drivers/net/usb/lan78xx.c:1040 lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1098 [inline] lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1949 [inline] lan78xx_reset+0x469/0x14c0 drivers/net/usb/lan78xx.c:3261 lan78xx_bind+0x562/0xd50 drivers/net/usb/lan78xx.c:3778 lan78xx_probe+0x1032/0x1c30 drivers/net/usb/lan78xx.c:4719 usb_probe_interface+0x668/0xc90 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0xad0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:801 driver_probe_device+0x4f/0x240 drivers/base/dd.c:831 __device_attach_driver+0x279/0x430 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:500 __device_attach+0x2b8/0x430 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:575 device_add+0x7b6/0xb80 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x2110 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c4/0x3c0 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26d/0xad0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:801 driver_probe_device+0x4f/0x240 drivers/base/dd.c:831 __device_attach_driver+0x279/0x430 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:500 __device_attach+0x2b8/0x430 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:575 device_add+0x7b6/0xb80 drivers/base/core.c:3689 usb_new_device+0xa39/0x1720 drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x29b1/0x4ef0 drivers/usb/core/hub.c:5953 process_one_work+0x94a/0x15d0 kernel/workqueue.c:3267 process_scheduled_works kernel/workqueue.c:3350 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3431 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245