Re: [syzbot] INFO: task hung in __input_unregister_device (4)

[syzbot <syzbot+deb6abc36aad4008f407@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: task hung in __input_unregister_device

INFO: task kworker/0:2:142 blocked for more than 143 seconds.
      Not tainted 5.19.0-rc4-syzkaller-00125-ga175eca0f3d7-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:D stack:24456 pid:  142 ppid:     2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6589
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa70/0x1350 kernel/locking/mutex.c:747
 input_disconnect_device drivers/input/input.c:785 [inline]
 __input_unregister_device+0x24/0x470 drivers/input/input.c:2235
 input_unregister_device+0xb4/0xf0 drivers/input/input.c:2430
 iforce_usb_disconnect+0x5e/0xf0 drivers/input/joystick/iforce/iforce-usb.c:261
 usb_unbind_interface+0x1d8/0x8e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:545 [inline]
 device_remove+0x11f/0x170 drivers/base/dd.c:537
 __device_release_driver drivers/base/dd.c:1222 [inline]
 device_release_driver_internal+0x4a1/0x700 drivers/base/dd.c:1248
 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:529
 device_del+0x4f3/0xc80 drivers/base/core.c:3604
 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1419
 usb_disconnect.cold+0x278/0x6ec drivers/usb/core/hub.c:2228
 hub_port_connect drivers/usb/core/hub.c:5207 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5507 [inline]
 port_event drivers/usb/core/hub.c:5663 [inline]
 hub_event+0x1e83/0x4690 drivers/usb/core/hub.c:5745
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 process_scheduled_works kernel/workqueue.c:2352 [inline]
 worker_thread+0x854/0x1080 kernel/workqueue.c:2438
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/28:
 #0: ffffffff8bd86660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491
6 locks held by kworker/0:2/142:
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff88801741b938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc900029bfda8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffff888147aaf190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #2: ffff888147aaf190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4690 drivers/usb/core/hub.c:5691
 #3: ffff88814713f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #3: ffff88814713f190 (&dev->mutex){....}-{3:3}, at: usb_disconnect.cold+0x43/0x6ec drivers/usb/core/hub.c:2219
 #4: ffff888147139118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #4: ffff888147139118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1054 [inline]
 #4: ffff888147139118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa0/0x700 drivers/base/dd.c:1245
 #5: ffff8881471382c0 (&dev->mutex#2){+.+.}-{3:3}, at: input_disconnect_device drivers/input/input.c:785 [inline]
 #5: ffff8881471382c0 (&dev->mutex#2){+.+.}-{3:3}, at: __input_unregister_device+0x24/0x470 drivers/input/input.c:2235
2 locks held by syslogd/2958:
 #0: ffff8880b9b39ed8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:544
 #1: ffffffff8bd86660 (rcu_read_lock){....}-{1:2}, at: inode_lock include/linux/fs.h:741 [inline]
 #1: ffffffff8bd86660 (rcu_read_lock){....}-{1:2}, at: generic_file_write_iter+0x8a/0x220 mm/filemap.c:3936
2 locks held by acpid/2961:
 #0: ffff888076e50158 (&joydev->mutex){+.+.}-{3:3}, at: joydev_close_device drivers/input/joydev.c:220 [inline]
 #0: ffff888076e50158 (&joydev->mutex){+.+.}-{3:3}, at: joydev_release+0x187/0x290 drivers/input/joydev.c:252
 #1: ffff8881471382c0 (&dev->mutex#2){+.+.}-{3:3}, at: input_close_device+0x42/0x1f0 drivers/input/input.c:727
2 locks held by getty/3289:
 #0: ffff88807ee70098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002d162e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2124
2 locks held by udevd/4091:
 #0: ffff88814ae63110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_open_device drivers/input/evdev.c:393 [inline]
 #0: ffff88814ae63110 (&evdev->mutex){+.+.}-{3:3}, at: evdev_open+0x2f3/0x6a0 drivers/input/evdev.c:487
 #1: ffff8881471382c0 (&dev->mutex#2){+.+.}-{3:3}, at: input_open_device+0x4a/0x320 drivers/input/input.c:656

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 5.19.0-rc4-syzkaller-00125-ga175eca0f3d7-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:369
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 5.19.0-rc4-syzkaller-00125-ga175eca0f3d7-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Workqueue: bat_events batadv_purge_orig
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:__local_bh_enable_ip+0x5d/0x120 kernel/softirq.c:378
Code: 03 83 c0 03 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 c5 00 00 00 8b 05 ff 76 73 0c 85 c0 74 0b 65 8b 05 f0 2a ba 7e 85 c0 74 53 9c <58> fa f6 c4 02 75 5a 65 8b 05 15 21 ba 7e 25 00 ff 00 00 3d 00 02
RSP: 0018:ffffc900000d7bd0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000201 RCX: 1ffffffff1b778a1
RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff891218b7
RBP: ffffffff891218b7 R08: 0000000000000000 R09: ffff8880703e0783
R10: ffffed100e07c0f0 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffc900000d7da8 R14: ffff8880119b7900 R15: 000000000000001e
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc54d501110 CR3: 000000000ba8e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_bh include/linux/spinlock.h:394 [inline]
 batadv_purge_orig_ref+0xeb7/0x1550 net/batman-adv/originator.c:1259
 batadv_purge_orig+0x17/0x60 net/batman-adv/originator.c:1272
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>
----------------
Code disassembly (best guess):
   0:	03 83 c0 03 0f b6    	add    -0x49f0fc40(%rbx),%eax
   6:	14 11                	adc    $0x11,%al
   8:	38 d0                	cmp    %dl,%al
   a:	7c 08                	jl     0x14
   c:	84 d2                	test   %dl,%dl
   e:	0f 85 c5 00 00 00    	jne    0xd9
  14:	8b 05 ff 76 73 0c    	mov    0xc7376ff(%rip),%eax        # 0xc737719
  1a:	85 c0                	test   %eax,%eax
  1c:	74 0b                	je     0x29
  1e:	65 8b 05 f0 2a ba 7e 	mov    %gs:0x7eba2af0(%rip),%eax        # 0x7eba2b15
  25:	85 c0                	test   %eax,%eax
  27:	74 53                	je     0x7c
  29:	9c                   	pushfq
* 2a:	58                   	pop    %rax <-- trapping instruction
  2b:	fa                   	cli
  2c:	f6 c4 02             	test   $0x2,%ah
  2f:	75 5a                	jne    0x8b
  31:	65 8b 05 15 21 ba 7e 	mov    %gs:0x7eba2115(%rip),%eax        # 0x7eba214d
  38:	25 00 ff 00 00       	and    $0xff00,%eax
  3d:	3d                   	.byte 0x3d
  3e:	00 02                	add    %al,(%rdx)


Tested on:

commit:         a175eca0 Merge tag 'drm-fixes-2022-07-01' of git://ano..
git tree:       http://kernel.source.codeaurora.cn/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=14c88434080000
kernel config:  https://syzkaller.appspot.com/x/.config?x=833001d0819ddbc9
dashboard link: https://syzkaller.appspot.com/bug?extid=deb6abc36aad4008f407
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17ed9168080000