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

From: syzbot
Date: Sun Jul 03 2022 - 10:11:16 EST


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/0:1:14 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/0:1 state:D stack:24296 pid: 14 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:793 [inline]
__input_unregister_device+0x24/0x470 drivers/input/input.c:2243
input_unregister_device+0xb4/0xf0 drivers/input/input.c:2438
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:
6 locks held by kworker/0:1/14:
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
#0: ffff8881458a0538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
#1: ffffc90000137da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
#2: ffff888020a04190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
#2: ffff888020a04190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4690 drivers/usb/core/hub.c:5691
#3: ffff888146de5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
#3: ffff888146de5190 (&dev->mutex){....}-{3:3}, at: usb_disconnect.cold+0x43/0x6ec drivers/usb/core/hub.c:2219
#4: ffff888146de3118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
#4: ffff888146de3118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1054 [inline]
#4: ffff888146de3118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa0/0x700 drivers/base/dd.c:1245
#5: ffff88807df402c0 (&dev->mutex#2){+.+.}-{3:3}, at: input_disconnect_device drivers/input/input.c:793 [inline]
#5: ffff88807df402c0 (&dev->mutex#2){+.+.}-{3:3}, at: __input_unregister_device+0x24/0x470 drivers/input/input.c:2243
1 lock held by khungtaskd/27:
#0: ffffffff8bd86660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491
2 locks held by acpid/2960:
#0: ffff88807dcec158 (&joydev->mutex){+.+.}-{3:3}, at: joydev_close_device drivers/input/joydev.c:220 [inline]
#0: ffff88807dcec158 (&joydev->mutex){+.+.}-{3:3}, at: joydev_release+0x187/0x290 drivers/input/joydev.c:252
#1: ffff88807df402c0 (&dev->mutex#2){+.+.}-{3:3}, at: input_close_device+0x44/0x220 drivers/input/input.c:733
2 locks held by getty/3285:
#0: ffff88814b110098 (&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
3 locks held by udevd/4093:
#0: ffff88807e905488 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:197 [inline]
#0: ffff88807e905488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x189/0x6e0 fs/kernfs/file.c:236
#1: ffff88806f5b50f0 (kn->active#86){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:198 [inline]
#1: ffff88806f5b50f0 (kn->active#86){++++}-{0:0}, at: kernfs_fop_read_iter+0x1ac/0x6e0 fs/kernfs/file.c:236
#2: ffff888146de5190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:840 [inline]
#2: ffff888146de5190 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:873

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4070 Comm: syz-executor.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
RIP: 0010:__pvclock_read_cycles arch/x86/include/asm/pvclock.h:86 [inline]
RIP: 0010:pvclock_clocksource_read+0x91/0x530 arch/x86/kernel/pvclock.c:76
Code: 43 08 8b 0b 48 bd 00 00 00 00 00 fc ff df 48 8d 7b 1c 48 89 44 24 10 48 c1 e8 03 48 8d 53 1b 49 89 c5 48 89 f8 48 89 7c 24 18 <4c> 8d 4b 0f 48 c1 e8 03 48 89 14 24 49 01 ed 4c 8d 43 18 48 01 e8
RSP: 0018:ffffc90002fafe20 EFLAGS: 00000806
RAX: ffffffff8f2ad05c RBX: ffffffff8f2ad040 RCX: 0000000000000004
RDX: ffffffff8f2ad05b RSI: 0000000000000000 RDI: ffffffff8f2ad05c
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff90680917
R10: fffffbfff20d0122 R11: 0000000000000001 R12: ffffffff8f2ad043
R13: 1ffffffff1e55a09 R14: 0000000000000000 R15: ffff88801d2824a8
FS: 0000555555f7a400(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555f7a708 CR3: 000000007435c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
kvm_clock_read arch/x86/kernel/kvmclock.c:79 [inline]
kvm_sched_clock_read+0x14/0x40 arch/x86/kernel/kvmclock.c:91
vtime_delta kernel/sched/cputime.c:637 [inline]
get_vtime_delta kernel/sched/cputime.c:646 [inline]
vtime_user_exit+0xbc/0x6c0 kernel/sched/cputime.c:720
__context_tracking_exit+0xb8/0xe0 kernel/context_tracking.c:160
user_exit_irqoff include/linux/context_tracking.h:47 [inline]
__enter_from_user_mode kernel/entry/common.c:24 [inline]
syscall_enter_from_user_mode+0x4c/0x70 kernel/entry/common.c:106
do_syscall_64+0x16/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7fbe204ade31
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 aa e7 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 e3 e7 ff ff 48 8b 04 24 eb 97 66 2e 0f 1f
RSP: 002b:00007fff04d571e0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 0000000000000085 RCX: 00007fbe204ade31
RDX: 00007fff04d57220 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff04d572ac R08: 0000000000000000 R09: 00007fff04dbc080
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032
R13: 000000000003dbc7 R14: 0000000000000000 R15: 00007fff04d57310
</TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 8b 0b mov (%rbx),%ecx
2: 48 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%rbp
9: fc ff df
c: 48 8d 7b 1c lea 0x1c(%rbx),%rdi
10: 48 89 44 24 10 mov %rax,0x10(%rsp)
15: 48 c1 e8 03 shr $0x3,%rax
19: 48 8d 53 1b lea 0x1b(%rbx),%rdx
1d: 49 89 c5 mov %rax,%r13
20: 48 89 f8 mov %rdi,%rax
23: 48 89 7c 24 18 mov %rdi,0x18(%rsp)
* 28: 4c 8d 4b 0f lea 0xf(%rbx),%r9 <-- trapping instruction
2c: 48 c1 e8 03 shr $0x3,%rax
30: 48 89 14 24 mov %rdx,(%rsp)
34: 49 01 ed add %rbp,%r13
37: 4c 8d 43 18 lea 0x18(%rbx),%r8
3b: 48 01 e8 add %rbp,%rax


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=15812020080000
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=16a4c000080000