From: syzbot <syzbot+f342ea16c9d06d80b585@syzkaller.appspotmail.com>
To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
linux-usb@vger.kernel.org, stern@rowland.harvard.edu,
sylv@sylv.io, syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [usb?] INFO: task hung in usb_port_suspend
Date: Fri, 11 Oct 2024 18:14:03 -0700 [thread overview]
Message-ID: <6709cd5b.050a0220.4cbc0.001a.GAE@google.com> (raw)
In-Reply-To: <b84d31a3-4353-4506-903a-04f1e1b8cbda@rowland.harvard.edu>
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: task hung in usb_port_suspend
INFO: task kworker/0:1:9 blocked for more than 143 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1 state:D stack:22896 pid:9 tgid:9 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
usb_kill_urb.part.0+0x1ca/0x250 drivers/usb/core/urb.c:713
usb_kill_urb+0x83/0xa0 drivers/usb/core/urb.c:702
usb_start_wait_urb+0x255/0x4c0 drivers/usb/core/message.c:65
usb_internal_control_msg drivers/usb/core/message.c:103 [inline]
usb_control_msg+0x327/0x4b0 drivers/usb/core/message.c:154
usb_enable_remote_wakeup drivers/usb/core/hub.c:3365 [inline]
usb_port_suspend+0x339/0xf10 drivers/usb/core/hub.c:3472
usb_generic_driver_suspend+0xeb/0x1d0 drivers/usb/core/generic.c:302
usb_suspend_device drivers/usb/core/driver.c:1272 [inline]
usb_suspend_both+0x66d/0x9c0 drivers/usb/core/driver.c:1443
usb_runtime_suspend+0x49/0x180 drivers/usb/core/driver.c:1968
__rpm_callback+0xc5/0x4c0 drivers/base/power/runtime.c:394
rpm_callback+0x192/0x1d0 drivers/base/power/runtime.c:448
rpm_suspend+0x2e7/0x1200 drivers/base/power/runtime.c:672
__pm_runtime_suspend+0xbc/0x160 drivers/base/power/runtime.c:1142
pm_runtime_put_sync_autosuspend include/linux/pm_runtime.h:524 [inline]
usb_new_device+0x1087/0x1a10 drivers/usb/core/hub.c:2683
hub_port_connect drivers/usb/core/hub.c:5521 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: task kworker/0:2:803 blocked for more than 143 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D stack:24064 pid:803 tgid:803 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578
usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
wdm_create+0x1269/0x1870 drivers/usb/class/cdc-wdm.c:1113
wdm_probe+0x239/0x2e0 drivers/usb/class/cdc-wdm.c:1165
usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254
usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651
hub_port_connect drivers/usb/core/hub.c:5521 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: task kworker/0:3:6535 blocked for more than 144 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3 state:D stack:24272 pid:6535 tgid:6535 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578
usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
wdm_create+0x1269/0x1870 drivers/usb/class/cdc-wdm.c:1113
wdm_probe+0x239/0x2e0 drivers/usb/class/cdc-wdm.c:1165
usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254
usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651
hub_port_connect drivers/usb/core/hub.c:5521 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: task kworker/0:4:6563 blocked for more than 144 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4 state:D stack:24704 pid:6563 tgid:6563 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578
usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
wdm_create+0x1269/0x1870 drivers/usb/class/cdc-wdm.c:1113
wdm_probe+0x239/0x2e0 drivers/usb/class/cdc-wdm.c:1165
usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254
usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:658
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:800
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459
__device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534
device_add+0x114b/0x1a70 drivers/base/core.c:3675
usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651
hub_port_connect drivers/usb/core/hub.c:5521 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
process_scheduled_works kernel/workqueue.c:3310 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: task syz.4.39:6580 blocked for more than 145 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.39 state:D stack:27856 pid:6580 tgid:6580 ppid:4263 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
rpm_resume+0x5a8/0x1330 drivers/base/power/runtime.c:834
rpm_resume+0x750/0x1330 drivers/base/power/runtime.c:892
__pm_runtime_resume+0xb6/0x170 drivers/base/power/runtime.c:1172
pm_runtime_resume_and_get include/linux/pm_runtime.h:430 [inline]
usb_autopm_get_interface+0x20/0xe0 drivers/usb/core/driver.c:1833
wdm_manage_power+0x1d/0xa0 drivers/usb/class/cdc-wdm.c:1134
wdm_release+0x26a/0x440 drivers/usb/class/cdc-wdm.c:779
__fput+0x3f6/0xb60 fs/file_table.c:431
task_work_run+0x14e/0x250 kernel/task_work.c:228
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x24e/0x260 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa49844dff9
RSP: 002b:00007fff7cd05398 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000001e9c1 RCX: 00007fa49844dff9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa498607a80 R08: 0000000000000001 R09: 00007fff7cd0568f
R10: 00007fa4982ca000 R11: 0000000000000246 R12: 000000000001ec9c
R13: 00007fff7cd054a0 R14: 0000000000000032 R15: ffffffffffffffff
</TASK>
INFO: task syz.0.40:6585 blocked for more than 145 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.40 state:D stack:28192 pid:6585 tgid:6582 ppid:4249 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752
wdm_open+0x5d/0x630 drivers/usb/class/cdc-wdm.c:715
usb_open+0x186/0x220 drivers/usb/core/file.c:47
chrdev_open+0x237/0x6a0 fs/char_dev.c:414
do_dentry_open+0x6cb/0x1390 fs/open.c:958
vfs_open+0x82/0x3f0 fs/open.c:1088
do_open fs/namei.c:3774 [inline]
path_openat+0x1e6a/0x2d60 fs/namei.c:3933
do_filp_open+0x1dc/0x430 fs/namei.c:3960
do_sys_openat2+0x17a/0x1e0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f087becc990
RSP: 002b:00007f087b948b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f087becc990
RDX: 0000000000000002 RSI: 00007f087b948c10 RDI: 00000000ffffff9c
RBP: 00007f087b948c10 R08: 0000000000000000 R09: 00007f087b948987
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f087c085f80 R15: 00007fff605cc188
</TASK>
INFO: task syz.3.41:6586 blocked for more than 146 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.41 state:D stack:28224 pid:6586 tgid:6583 ppid:4258 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x124/0x330 kernel/locking/rwsem.c:1526
usb_open+0x23/0x220 drivers/usb/core/file.c:38
chrdev_open+0x237/0x6a0 fs/char_dev.c:414
do_dentry_open+0x6cb/0x1390 fs/open.c:958
vfs_open+0x82/0x3f0 fs/open.c:1088
do_open fs/namei.c:3774 [inline]
path_openat+0x1e6a/0x2d60 fs/namei.c:3933
do_filp_open+0x1dc/0x430 fs/namei.c:3960
do_sys_openat2+0x17a/0x1e0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7ff07ac990
RSP: 002b:00007f7ff022eb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f7ff07ac990
RDX: 0000000000000002 RSI: 00007f7ff022ec10 RDI: 00000000ffffff9c
RBP: 00007f7ff022ec10 R08: 0000000000000000 R09: 00007f7ff022e987
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7ff0965f80 R15: 00007ffc7915f428
</TASK>
INFO: task syz.1.42:6587 blocked for more than 146 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.42 state:D stack:28192 pid:6587 tgid:6584 ppid:4250 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x124/0x330 kernel/locking/rwsem.c:1526
usb_open+0x23/0x220 drivers/usb/core/file.c:38
chrdev_open+0x237/0x6a0 fs/char_dev.c:414
do_dentry_open+0x6cb/0x1390 fs/open.c:958
vfs_open+0x82/0x3f0 fs/open.c:1088
do_open fs/namei.c:3774 [inline]
path_openat+0x1e6a/0x2d60 fs/namei.c:3933
do_filp_open+0x1dc/0x430 fs/namei.c:3960
do_sys_openat2+0x17a/0x1e0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9bb1bc990
RSP: 002b:00007ff9bac3eb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007ff9bb1bc990
RDX: 0000000000000002 RSI: 00007ff9bac3ec10 RDI: 00000000ffffff9c
RBP: 00007ff9bac3ec10 R08: 0000000000000000 R09: 00007ff9bac3e987
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff9bb375f80 R15: 00007ffc4d422d68
</TASK>
INFO: task syz.2.43:6589 blocked for more than 146 seconds.
Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.43 state:D stack:28288 pid:6589 tgid:6588 ppid:4253 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5315 [inline]
__schedule+0x105f/0x34b0 kernel/sched/core.c:6675
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6767
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824
rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x124/0x330 kernel/locking/rwsem.c:1526
usb_open+0x23/0x220 drivers/usb/core/file.c:38
chrdev_open+0x237/0x6a0 fs/char_dev.c:414
do_dentry_open+0x6cb/0x1390 fs/open.c:958
vfs_open+0x82/0x3f0 fs/open.c:1088
do_open fs/namei.c:3774 [inline]
path_openat+0x1e6a/0x2d60 fs/namei.c:3933
do_filp_open+0x1dc/0x430 fs/namei.c:3960
do_sys_openat2+0x17a/0x1e0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fab01e9c990
RSP: 002b:00007fab01918b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fab01e9c990
RDX: 0000000000000002 RSI: 00007fab01918c10 RDI: 00000000ffffff9c
RBP: 00007fab01918c10 R08: 0000000000000000 R09: 00007fab01918987
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fab02055f80 R15: 00007ffc5d3515e8
</TASK>
Showing all locks held in the system:
4 locks held by kworker/0:1/9:
#0: ffff8881062c3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc9000009fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
#2: ffff888109ba5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#2: ffff888109ba5190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849
#3: ffff888109bb0508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline]
#3: ffff888109bb0508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_port_suspend+0x255/0xf10 drivers/usb/core/hub.c:3463
1 lock held by khungtaskd/30:
#0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
6 locks held by kworker/0:2/803:
#0: ffff8881062c3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc90001e0fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
#2: ffff888106b7e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#2: ffff888106b7e190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849
#3: ffff888113f6f190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#3: ffff888113f6f190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#4: ffff88811dfcd160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#4: ffff88811dfcd160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#5: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
2 locks held by getty/2605:
#0: ffff8881146210a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
6 locks held by kworker/0:3/6535:
#0: ffff8881062c3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc900018a7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
#2: ffff8881097ae190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#2: ffff8881097ae190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849
#3: ffff888113f6e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#3: ffff888113f6e190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#4: ffff88811dfcb160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#4: ffff88811dfcb160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#5: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
6 locks held by kworker/0:4/6563:
#0: ffff8881062c3548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
#1: ffffc90001477d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
#2: ffff888109b21190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#2: ffff888109b21190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849
#3: ffff88811dfcf190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#3: ffff88811dfcf190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#4: ffff888127339160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline]
#4: ffff888127339160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005
#5: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134
1 lock held by syz.4.39/6580:
#0: ffffffff89a967e8 (wdm_mutex){+.+.}-{3:3}, at: wdm_release+0x4b/0x440 drivers/usb/class/cdc-wdm.c:764
2 locks held by syz.0.40/6585:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
#1: ffffffff89a967e8 (wdm_mutex){+.+.}-{3:3}, at: wdm_open+0x5d/0x630 drivers/usb/class/cdc-wdm.c:715
1 lock held by syz.3.41/6586:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.1.42/6587:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.2.43/6589:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.4.44/8607:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.3.48/8849:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.0.45/8866:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.1.46/8871:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.2.47/8874:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.4.49/10394:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.1.51/11122:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.0.50/11142:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.3.53/11167:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.2.52/11181:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.4.54/11615:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.1.55/13538:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.3.58/13772:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.0.56/13774:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.2.57/13777:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.4.59/13902:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.1.60/15429:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.0.61/16122:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.2.62/16144:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.3.63/16153:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
1 lock held by syz.4.64/16188:
#0: ffffffff899dadb0 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38
3 locks held by modprobe/16364:
#0: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:593 [inline]
#0: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1505 [inline]
#0: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1804 [inline]
#0: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x293/0x34b0 kernel/sched/core.c:6575
#1: ffff88810be8a518 (&sighand->siglock){....}-{2:2}, at: do_notify_parent+0x778/0x1040 kernel/signal.c:2114
#2: ffff8881007d47b8 (&sig->wait_chldexit){....}-{2:2}, at: __wake_up_common_lock kernel/sched/wait.c:105 [inline]
#2: ffff8881007d47b8 (&sig->wait_chldexit){....}-{2:2}, at: __wake_up_sync_key+0x1c/0x50 kernel/sched/wait.c:173
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xf0c/0x1240 kernel/hung_task.c:379
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16371 Comm: modprobe Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:_compound_head include/linux/page-flags.h:244 [inline]
RIP: 0010:virt_to_folio include/linux/mm.h:1284 [inline]
RIP: 0010:virt_to_slab mm/slab.h:206 [inline]
RIP: 0010:kmem_cache_free+0x99/0x480 mm/slub.c:4682
Code: 48 89 df 48 89 44 24 10 e8 74 c3 6f ff 48 c1 e8 0c 49 89 c2 48 b8 00 00 00 00 00 ea ff ff 49 c1 e2 06 4d 8d 34 02 49 8b 46 08 <a8> 01 0f 85 62 02 00 00 0f 1f 44 00 00 31 c0 41 80 7e 33 f5 48 89
RSP: 0018:ffffc90004d5fd20 EFLAGS: 00000202
RAX: ffffea00046f2801 RBX: ffff88811bca6600 RCX: ffffffff8116adac
RDX: ffff888115f09d40 RSI: ffffffff8116adb6 RDI: 0000000000000007
RBP: ffffc90004d5fd80 R08: 0000000000000007 R09: 0000000000000000
R10: 00000000046f2980 R11: 0000000000000000 R12: ffff888100add140
R13: 000000000003c40c R14: ffffea00046f2980 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881f5900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76c8ff3270 CR3: 000000011a3fa000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
putname+0x12e/0x170 fs/namei.c:280
do_sys_openat2+0x160/0x1e0 fs/open.c:1423
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f76c929aa46
Code: 10 00 00 00 44 8b 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 44 89 c2 4c 89 ce bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 0a 48 01 00 48 83 c8 ff c3 31
RSP: 002b:00007ffe0b165df8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffe0b166058 RCX: 00007f76c929aa46
RDX: 0000000000080000 RSI: 00007ffe0b165e70 RDI: 00000000ffffff9c
RBP: 00007ffe0b165e60 R08: 0000000000080000 R09: 00007ffe0b165e70
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffe0b165e70
R13: 0000000000000005 R14: 00007ffe0b16603f R15: 00000000ffffffff
</TASK>
Tested on:
commit: 4a9fe2a8 dt-bindings: usb: dwc3-imx8mp: add compatible..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=112c305f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=4510af5d637450fb
dashboard link: https://syzkaller.appspot.com/bug?extid=f342ea16c9d06d80b585
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=147e3b27980000
next prev parent reply other threads:[~2024-10-12 1:14 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-11 13:08 [syzbot] [usb?] INFO: task hung in usb_port_suspend syzbot
2024-10-11 14:08 ` Alan Stern
2024-10-11 14:35 ` syzbot
2024-10-11 14:55 ` Alan Stern
2024-10-11 15:00 ` syzbot
2024-10-11 15:17 ` Alan Stern
2024-10-11 15:45 ` syzbot
2024-10-12 0:48 ` Alan Stern
2024-10-12 1:14 ` syzbot [this message]
2024-10-13 1:09 ` Alan Stern
2024-10-13 2:10 ` syzbot
2024-10-13 2:43 ` Alan Stern
2024-10-13 3:05 ` syzbot
2024-10-13 14:30 ` Alan Stern
2024-10-13 15:02 ` syzbot
2024-10-13 15:45 ` Alan Stern
2024-10-13 16:14 ` syzbot
2024-10-13 18:02 ` Alan Stern
2024-10-13 18:38 ` syzbot
2024-10-13 19:24 ` Alan Stern
2024-10-13 20:34 ` syzbot
2024-10-14 1:24 ` [syzbot] " syzbot
2024-10-20 16:38 ` syzbot
2024-10-21 8:04 ` Oliver Neukum
2024-10-21 13:37 ` Alan Stern
2024-10-22 11:42 ` Hillf Danton
2024-10-22 10:46 ` Hillf Danton
2024-10-22 11:29 ` syzbot
[not found] <b9bea8cd-effc-484f-ac46-1644093adffe@rowland.harvard.edu>
2024-10-14 1:58 ` syzbot
2024-10-14 16:14 ` Alan Stern
2024-10-14 17:20 ` syzbot
2024-10-14 18:21 ` Alan Stern
2024-10-14 18:42 ` syzbot
2024-10-14 22:38 ` Alan Stern
2024-10-14 22:57 ` syzbot
2024-10-15 0:43 ` Alan Stern
2024-10-15 0:45 ` syzbot
2024-10-15 1:31 ` Alan Stern
2024-10-15 14:22 ` Alan Stern
2024-10-15 14:54 ` syzbot
2024-10-15 19:23 ` Alan Stern
2024-10-15 19:54 ` syzbot
2024-10-16 0:54 ` Alan Stern
2024-10-16 1:54 ` syzbot
2024-10-16 2:11 ` Alan Stern
2024-10-16 2:34 ` syzbot
2024-10-16 14:40 ` Alan Stern
2024-10-16 15:02 ` syzbot
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--in-reply-to=6709cd5b.050a0220.4cbc0.001a.GAE@google.com \
--to=syzbot+f342ea16c9d06d80b585@syzkaller.appspotmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=stern@rowland.harvard.edu \
--cc=sylv@sylv.io \
--cc=syzkaller-bugs@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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