INFO: task syz-executor.4:11911 blocked for more than 143 seconds. Not tainted 5.9.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:28744 pid:11911 ppid: 7116 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion_timeout+0x15e/0x270 kernel/sched/completion.c:157 usb_start_wait_urb+0x144/0x2b0 drivers/usb/core/message.c:63 usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:254 do_proc_bulk+0x39b/0x710 drivers/usb/core/devio.c:1231 proc_bulk drivers/usb/core/devio.c:1268 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2542 [inline] usbdev_ioctl+0x586/0x3360 drivers/usb/core/devio.c:2708 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f124a289c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000001aa40 RCX: 000000000045d5b9 RDX: 00000000200001c0 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 000000000169fb6f R14: 00007f124a28a9c0 R15: 000000000118cf4c Showing all locks held in the system: 1 lock held by khungtaskd/1169: #0: ffffffff89bd6a40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829 1 lock held by systemd-journal/3884: 1 lock held by in:imklog/6525: #0: ffff88809531b5f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 3 locks held by rs:main Q:Reg/6526: #0: ffff8880ae635e18 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae635e18 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x270/0x2230 kernel/sched/core.c:4445 #1: ffff88809897a450 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2783 [inline] #1: ffff88809897a450 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x54f/0x730 fs/read_write.c:574 #2: ffff88808ab87588 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:779 [inline] #2: ffff88808ab87588 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: ext4_buffered_write_iter+0xb3/0x4a0 fs/ext4/file.c:263 2 locks held by agetty/6756: #0: ffff8880a32d2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f702e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 2 locks held by agetty/6757: #0: ffff8880a2a44098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f742e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1169 Comm: khungtaskd Not tainted 5.9.0-rc4-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+0x198/0x1fd lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 182 Comm: kworker/u4:3 Not tainted 5.9.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:398 [inline] RIP: 0010:lock_is_held_type+0xa8/0xf0 kernel/locking/lockdep.c:5046 Code: 00 00 83 f9 ff 74 11 41 0f b6 46 22 45 31 e4 83 e0 03 39 c8 41 0f 94 c4 65 48 8b 14 25 c0 fe 01 00 8b 82 e4 08 00 00 83 e8 01 <66> 85 c0 89 82 e4 08 00 00 75 27 4c 89 ff e8 35 b9 64 f9 48 83 c4 RSP: 0018:ffffc900016b7af8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 1ffffffff1308b20 RDX: ffff8880a8cd83c0 RSI: ffffffff89bd6980 RDI: ffff8880a8cd8cf8 RBP: ffff8880a8cd83c0 R08: 0000000000000000 R09: ffffffff8ab26b8f R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880a8cd8ca8 R14: ffff8880a8cd8cf8 R15: 0000000000000282 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1793e80000 CR3: 0000000096550000 CR4: 00000000001526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:267 [inline] rcu_read_lock_sched_held+0x3a/0xb0 kernel/rcu/update.c:136 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x6a1/0x8f0 kernel/locking/lockdep.c:5017 rcu_lock_release include/linux/rcupdate.h:246 [inline] rcu_read_unlock include/linux/rcupdate.h:688 [inline] batadv_nc_process_nc_paths.part.0+0x267/0x3b0 net/batman-adv/network-coding.c:698 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:678 [inline] batadv_nc_worker+0xb90/0xe50 net/batman-adv/network-coding.c:734 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294