INFO: task syz-executor.2:4701 blocked for more than 143 seconds. Not tainted 5.3.0-rc7+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28904 4701 1753 0x00000004 Call Trace: schedule+0xca/0x250 kernel/sched/core.c:3947 schedule_timeout+0x440/0xb20 kernel/time/timer.c:1807 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion_timeout+0x282/0x3e0 kernel/sched/completion.c:155 usb_start_wait_urb+0x14b/0x2b0 drivers/usb/core/message.c:62 usb_internal_control_msg drivers/usb/core/message.c:101 [inline] usb_control_msg+0x31c/0x4a0 drivers/usb/core/message.c:152 ld_usb_write+0x856/0xa10 drivers/usb/misc/ldusb.c:577 __vfs_write+0x76/0x100 fs/read_write.c:494 vfs_write+0x262/0x5c0 fs/read_write.c:558 ksys_write+0x1e8/0x250 fs/read_write.c:611 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4598e9 Code: 70 c0 00 48 83 fb 10 7c 54 48 89 f7 48 83 fb 20 0f 87 8d 00 00 00 48 8d 44 1e f0 eb 15 f3 0f 6f 0f 66 0f 74 c8 66 0f d7 d1 0f d2 75 25 48 83 c7 10 48 39 c7 72 e6 48 89 c7 f3 0f 6f 08 66 0f RSP: 002b:00007fab3593ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004598e9 RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fab3593f6d4 R13: 00000000004c9a9b R14: 00000000004e11a8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: 00000000d930c278 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5254 1 lock held by rsyslogd/1605: #0: 00000000644248fd (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1695: #0: 00000000ae648ca0 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000005a785656 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1696: #0: 000000001f5bbeb6 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000005d0aa585 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1697: #0: 000000002aee82a4 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000005e4ba870 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1698: #0: 0000000052e5b95f (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000c80c54a2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1699: #0: 000000009592cf16 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000637232c9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1700: #0: 000000004b5f3975 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000039288560 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1701: #0: 000000000fd0b3fe (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000c7d8633d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/4701: #0: 00000000ddff1c41 (&dev->mutex#4){+.+.}, at: ld_usb_write+0x111/0xa10 drivers/usb/misc/ldusb.c:539 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.3.0-rc7+ #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+0xca/0x13e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9a4/0xe50 kernel/hung_task.c:289 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2750 Comm: kworker/0:4 Not tainted 5.3.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_power_efficient gc_worker RIP: 0010:test_bit include/asm-generic/bitops-instrumented.h:237 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:163 [inline] RIP: 0010:__lock_acquire+0x1688/0x3b50 kernel/locking/lockdep.c:3876 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 09 3c 03 7f 05 e8 05 41 3f 00 41 0f b7 5f f8 66 81 e3 ff 1f 0f b7 db 08 00 00 00 48 89 d8 48 c1 f8 06 48 8d 3c c5 80 bc d6 88 e8 3f RSP: 0018:ffff8881d4affad0 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000329 RCX: bb55c10a9f7282c7 RDX: 1ffff1103a85b412 RSI: 00000000878d9e56 RDI: ffff8881d42da090 RBP: ffff8881d42d9800 R08: 0000000000000000 R09: fffffbfff11ad791 R10: fffffbfff11ad790 R11: ffffffff88d6bc87 R12: 00000000dba4fcd2 R13: 1ec4ebd55b261ad6 R14: ffffffff8789f6b0 R15: ffff8881d42da098 FS: 0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001a32000 CR3: 00000001d67c1000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x127/0x320 kernel/locking/lockdep.c:4412 rcu_lock_acquire include/linux/rcupdate.h:208 [inline] rcu_read_lock include/linux/rcupdate.h:592 [inline] gc_worker+0x18d/0xcb0 net/netfilter/nf_conntrack_core.c:1246 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 worker_thread+0x96/0xe20 kernel/workqueue.c:2415 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352