INFO: task syz.8.1805:13525 blocked for more than 143 seconds. Not tainted 6.14.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.1805 state:D stack:23872 pid:13525 tgid:13525 ppid:7966 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 device_lock include/linux/device.h:1030 [inline] usbdev_release+0x77/0x7a0 drivers/usb/core/devio.c:1099 __fput+0x3e9/0x9f0 fs/file_table.c:464 task_work_run+0x24f/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/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9f6ed8d169 RSP: 002b:00007f9f6f0cfb88 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f9f6efa7ba0 RCX: 00007f9f6ed8d169 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f9f6efa7ba0 R08: 000000000000020c R09: 0000001e6f0cfe7f R10: 00007f9f6efa7ac0 R11: 0000000000000246 R12: 000000000005a10a R13: 00007f9f6efa6080 R14: ffffffffffffffff R15: 00007f9f6f0cfca0 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90000107c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000107c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 1 lock held by khungtaskd/30: #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 2 locks held by getty/5589: #0: ffff8880352490a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 8 locks held by kworker/0:3/5877: 3 locks held by kworker/1:8/9523: #0: ffff888145289d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888145289d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc900033bfc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900033bfc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff88802862a190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #2: ffff88802862a190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861 1 lock held by syz.8.1805/13525: #0: ffff888028411190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #0: ffff888028411190 (&dev->mutex){....}-{4:4}, at: usbdev_release+0x77/0x7a0 drivers/usb/core/devio.c:1099 5 locks held by kworker/u8:16/14111: #0: ffff88801bef5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801bef5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90003e1fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003e1fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fec8a10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606 #3: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x880 net/core/dev.c:12423 #4: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline] #4: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x820 kernel/rcu/tree_exp.h:996 1 lock held by syz.2.2411/16855: #0: ffff888028411190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #0: ffff888028411190 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x156/0x770 drivers/usb/core/devio.c:1054 2 locks held by syz-executor/16951: #0: ffffffff8f676340 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8f676340 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8f676340 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564 #1: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline] #1: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021 1 lock held by syz.4.2438/17004: #0: ffffffff8eb3e300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3741 1 lock held by syz.0.2440/17012: #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x86e/0x1340 net/core/dev_ioctl.c:852 1 lock held by syz.0.2440/17014: #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6918 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc4-syzkaller #0 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+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 5877 Comm: kworker/0:3 Not tainted 6.14.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416 Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 4c 23 a5 fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7 RSP: 0018:ffffc90004c66070 EFLAGS: 00000002 RAX: 0000000000000037 RBX: ffffffff9a9960a0 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 00000000000fffff RDI: 0000000000100000 RBP: 0000000000000000 R08: ffffffff8583d4cb R09: 1ffff110049af046 R10: dffffc0000000000 R11: ffffffff8583d480 R12: dffffc0000000000 R13: 0000000000000037 R14: 0000000000000037 R15: 00000000000003f8 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff879c6000 CR3: 000000007f964000 CR4: 00000000003526f0 DR0: 0000000000000008 DR1: 00000000000000ff DR2: fffffffffffffffb DR3: 3e00000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_write+0x1430/0x1e00 drivers/tty/serial/8250/8250_port.c:3465 console_emit_next_record kernel/printk/printk.c:3122 [inline] console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 dev_vprintk_emit+0x341/0x400 drivers/base/core.c:4890 dev_printk_emit+0xdd/0x120 drivers/base/core.c:4901 __netdev_printk+0x3e0/0x4d0 net/core/dev.c:12302 netdev_err+0x122/0x170 net/core/dev.c:12354 asix_set_sw_mii drivers/net/usb/asix_common.c:78 [inline] asix_check_host_enable drivers/net/usb/asix_common.c:98 [inline] __asix_mdio_read drivers/net/usb/asix_common.c:506 [inline] asix_mdio_read+0x25c/0x620 drivers/net/usb/asix_common.c:529 asix_phy_reset+0xc6/0x1b0 drivers/net/usb/asix_devices.c:215 ax88172_bind+0x436/0x600 drivers/net/usb/asix_devices.c:275 usbnet_probe+0xa26/0x27a0 drivers/net/usb/usbnet.c:1761 usb_probe_interface+0x641/0xbb0 drivers/usb/core/driver.c:396 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+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x333/0x520 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3665 usb_set_configuration+0x1976/0x1fb0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x88/0x140 drivers/usb/core/generic.c:250 usb_probe_device+0x1b8/0x380 drivers/usb/core/driver.c:291 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+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x333/0x520 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3665 usb_new_device+0x104a/0x19a0 drivers/usb/core/hub.c:2663 hub_port_connect drivers/usb/core/hub.c:5533 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x2d6d/0x5150 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244