INFO: task kworker/1:0:29458 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:0 D25696 29458 2 0x80000000 team0: Port device bridge1898 added Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 team0: Port device bridge1882 added schedule+0x8d/0x1b0 kernel/sched/core.c:3561 usb_kill_urb.part.0+0x197/0x220 drivers/usb/core/urb.c:697 usb_kill_urb+0x7c/0x90 drivers/usb/core/urb.c:692 usb_start_wait_urb+0x252/0x4c0 drivers/usb/core/message.c:63 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152 usb_get_descriptor+0xc5/0x1b0 drivers/usb/core/message.c:654 usb_get_device_descriptor+0x81/0xf0 drivers/usb/core/message.c:926 hub_port_init+0x74b/0x3120 drivers/usb/core/hub.c:4799 hub_port_connect drivers/usb/core/hub.c:5070 [inline] hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] port_event drivers/usb/core/hub.c:5361 [inline] hub_event+0x1ccd/0x44a0 drivers/usb/core/hub.c:5441 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 1 lock held by khungtaskd/1569: #0: 00000000e614e6bb (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by systemd-udevd/4699: 1 lock held by in:imklog/7746: #0: 0000000083742d6e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 5 locks held by kworker/1:0/29458: team0: Port device bridge1883 added #0: 0000000015be1f6d ((wq_completion)"usb_hub_wq"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000b4fd9e1b ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 team0: Port device bridge1899 added #2: 00000000f474bcc9 (&dev->mutex){....}, at: device_lock include/linux/device.h:1174 [inline] #2: 00000000f474bcc9 (&dev->mutex){....}, at: hub_event+0x11e/0x44a0 drivers/usb/core/hub.c:5387 #3: 0000000075e0547d (&port_dev->status_lock){+.+.}, at: usb_lock_port drivers/usb/core/hub.c:2983 [inline] #3: 0000000075e0547d (&port_dev->status_lock){+.+.}, at: hub_port_connect drivers/usb/core/hub.c:5069 [inline] #3: 0000000075e0547d (&port_dev->status_lock){+.+.}, at: hub_port_connect_change drivers/usb/core/hub.c:5253 [inline] #3: 0000000075e0547d (&port_dev->status_lock){+.+.}, at: port_event drivers/usb/core/hub.c:5361 [inline] #3: 0000000075e0547d (&port_dev->status_lock){+.+.}, at: hub_event+0x1cb8/0x44a0 drivers/usb/core/hub.c:5441 #4: 00000000ea28d54c (hcd->address0_mutex){+.+.}, at: hub_port_init+0x1b9/0x3120 drivers/usb/core/hub.c:4578 1 lock held by syz-executor.0/8126: #0: 000000004c1827b4 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: 000000004c1827b4 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667 1 lock held by syz-executor.5/8117: #0: 0000000092f7ecb4 (&mm->mmap_sem){++++}, at: __do_page_fault+0x97f/0xd60 arch/x86/mm/fault.c:1348 1 lock held by syz-executor.5/8122: 2 locks held by syz-executor.1/8119: #0: 000000009d9b5c3e (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000009d9b5c3e (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 #1: 000000004c1827b4 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: 000000004c1827b4 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x256/0x6f0 kernel/rcu/tree_exp.h:667 1 lock held by syz-executor.4/8124: #0: 00000000968cebe3 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000968cebe3 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1569 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8151 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:hlock_class kernel/locking/lockdep.c:145 [inline] RIP: 0010:mark_lock+0x4b/0x1160 kernel/locking/lockdep.c:3106 Code: 48 c1 ea 03 41 bc 01 00 00 00 55 41 d3 e4 48 89 f5 53 48 83 ec 18 0f b6 04 02 84 c0 74 08 3c 01 0f 8e f1 07 00 00 0f b7 45 20 <66> a9 ff 1f 74 7c 48 ba 00 00 00 00 00 fc ff df 4c 89 f1 48 c1 e9 RSP: 0018:ffff8881e19bfa18 EFLAGS: 00000046 RAX: 0000000000000450 RBX: 0000000000000000 RCX: 0000000000000003 RDX: 1ffff110129b3dcd RSI: ffff888094d9ee48 RDI: ffff888094d9e5c0 RBP: ffff888094d9ee48 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008 R13: ffff888094d9e5c0 R14: ffff888094d9ee68 R15: 0000000000000003 FS: 00005555572ba400(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe344035020 CR3: 00000001f3550000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_held_locks+0xa6/0xf0 kernel/locking/lockdep.c:2810 __trace_hardirqs_on_caller kernel/locking/lockdep.c:2831 [inline] lockdep_hardirqs_on+0x288/0x5c0 kernel/locking/lockdep.c:2884 lookup_bh_lru fs/buffer.c:1279 [inline] __find_get_block+0x24b/0xde0 fs/buffer.c:1291 sb_find_get_block include/linux/buffer_head.h:346 [inline] recently_deleted fs/ext4/ialloc.c:684 [inline] find_inode_bit+0x213/0x520 fs/ext4/ialloc.c:724 __ext4_new_inode+0x160c/0x5a20 fs/ext4/ialloc.c:916 ext4_symlink+0x3f5/0xc00 fs/ext4/namei.c:3176 vfs_symlink+0x453/0x6c0 fs/namei.c:4129 do_symlinkat+0x258/0x2c0 fs/namei.c:4156 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f99901907a7 Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff3363adc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f99901907a7 RDX: 00007fff3363aea7 RSI: 00007f99901eb0dd RDI: 00007fff3363ae90 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff3363ac60 R10: 00007fff3363ab17 R11: 0000000000000202 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007fff3363ae90 ---------------- Code disassembly (best guess): 0: 48 c1 ea 03 shr $0x3,%rdx 4: 41 bc 01 00 00 00 mov $0x1,%r12d a: 55 push %rbp b: 41 d3 e4 shl %cl,%r12d e: 48 89 f5 mov %rsi,%rbp 11: 53 push %rbx 12: 48 83 ec 18 sub $0x18,%rsp 16: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax 1a: 84 c0 test %al,%al 1c: 74 08 je 0x26 1e: 3c 01 cmp $0x1,%al 20: 0f 8e f1 07 00 00 jle 0x817 26: 0f b7 45 20 movzwl 0x20(%rbp),%eax * 2a: 66 a9 ff 1f test $0x1fff,%ax <-- trapping instruction 2e: 74 7c je 0xac 30: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 37: fc ff df 3a: 4c 89 f1 mov %r14,%rcx 3d: 48 rex.W 3e: c1 .byte 0xc1 3f: e9 .byte 0xe9