INFO: task syz-executor.2:14925 blocked for more than 143 seconds. Not tainted 5.4.0-rc5+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28904 14925 1734 0x00000004 Call Trace: schedule+0xca/0x250 kernel/sched/core.c:4136 schedule_timeout+0x440/0xb20 kernel/time/timer.c:1895 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+0x87b/0xa20 drivers/usb/misc/ldusb.c:576 __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:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f49 Code: 0f 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 <0f> 11 07 48 83 c7 10 0f 10 06 48 83 c6 10 0f 11 07 48 83 c7 10 0f RSP: 002b:00007fc34db58c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f49 RDX: 00000000fffffef3 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc34db596d4 R13: 00000000004ca679 R14: 00000000004e2808 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: ffffffff86cfe8a0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5335 1 lock held by rsyslogd/1594: #0: ffff8881d30d34e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:801 2 locks held by getty/1684: #0: ffff8881d232a090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004692e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1685: #0: ffff8881d1a00090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000047d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1686: #0: ffff8881d278e090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000045d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1687: #0: ffff8881d1a03090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004852e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1688: #0: ffff8881d1a21090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004752e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1689: #0: ffff8881d232b090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000046d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1690: #0: ffff8881d2788090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000044d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.2/14925: #0: ffff8881d3e41c60 (&dev->mutex#4){+.+.}, at: ld_usb_write+0x111/0xa20 drivers/usb/misc/ldusb.c:538 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.4.0-rc5+ #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: 0 Comm: swapper/0 Not tainted 5.4.0-rc5+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline] RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:2861 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2881 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2936 [inline] RIP: 0010:__lock_acquire+0x149d/0x3b60 kernel/locking/lockdep.c:3955 Code: 86 c8 61 48 b8 00 00 00 00 00 fc ff df 48 0f af 4c 24 30 48 c1 e9 31 4c 8d 04 cd 80 dc d0 88 4c 89 c2 48 c1 ea 03 80 3c 02 00 <0f> 85 c4 23 00 00 48 8b 1c cd 80 dc d0 88 48 85 db 74 5f 48 83 eb RSP: 0018:ffff8881db209a48 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000000027 RCX: 00000000000043a5 RDX: 1ffffffff11a5f35 RSI: 0000000000000008 RDI: ffffffff88d59d20 RBP: ffffffff86c2b200 R08: ffffffff88d2f9a8 R09: fffffbfff11ab3a5 R10: fffffbfff11ab3a4 R11: ffffffff88d59d27 R12: 000000009c4ed385 R13: 6d051119bc332348 R14: ffffffff87867fb0 R15: ffffffff86c2ba78 FS: 0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001d51b5000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x127/0x320 kernel/locking/lockdep.c:4487 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x32/0x50 kernel/locking/spinlock.c:159 rq_lock_irqsave kernel/sched/sched.h:1199 [inline] load_balance+0x794/0x24e0 kernel/sched/fair.c:8835 rebalance_domains+0x600/0xaa0 kernel/sched/fair.c:9230 _nohz_idle_balance+0x336/0x3f0 kernel/sched/fair.c:9643 __do_softirq+0x221/0x912 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x178/0x1a0 kernel/softirq.c:413 reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:854 RIP: 0010:default_idle+0x28/0x2e0 arch/x86/kernel/process.c:581 Code: 90 90 41 56 41 55 65 44 8b 2d 74 ee 91 7a 41 54 55 53 0f 1f 44 00 00 e8 26 ad d3 fb e9 07 00 00 00 0f 00 2d aa 93 52 00 fb f4 <65> 44 8b 2d 50 ee 91 7a 0f 1f 44 00 00 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffffff86c07da8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02 RAX: 0000000000000007 RBX: ffffffff86c2b200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffffffff86c2ba4c RBP: fffffbfff0d85640 R08: ffffffff86c2b200 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x3b6/0x500 kernel/sched/idle.c:263 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:355 start_kernel+0x82a/0x864 init/main.c:784 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241