From: syzbot <syzbot+fd9d03311cdce9a9ec36@syzkaller.appspotmail.com>
To: andreyknvl@google.com, linux-usb@vger.kernel.org,
oneukum@suse.com, syzkaller-bugs@googlegroups.com,
thomas@winischhofer.net
Subject: Re: [syzbot] INFO: task hung in sisusb_open
Date: Wed, 27 Oct 2021 05:28:14 -0700 [thread overview]
Message-ID: <0000000000006405cf05cf54bacb@google.com> (raw)
In-Reply-To: <bf8eefe4-7fe1-002f-8258-10a3e825856a@suse.com>
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: task hung in usb_register_dev
INFO: task kworker/1:0:20 blocked for more than 143 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0 state:D stack:24904 pid: 20 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107
__down_write_common kernel/locking/rwsem.c:1262 [inline]
__down_write_common kernel/locking/rwsem.c:1259 [inline]
__down_write kernel/locking/rwsem.c:1271 [inline]
down_write+0x137/0x150 kernel/locking/rwsem.c:1518
usb_register_dev drivers/usb/core/file.c:187 [inline]
usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
sisusb_probe+0x21c/0xbe3 drivers/usb/misc/sisusbvga/sisusb.c:3039
usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_set_configuration+0x113f/0x1910 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
hub_port_connect drivers/usb/core/hub.c:5348 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5488 [inline]
port_event drivers/usb/core/hub.c:5634 [inline]
hub_event+0x2357/0x4330 drivers/usb/core/hub.c:5716
process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INFO: task kworker/0:3:2954 blocked for more than 143 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:3 state:D stack:25256 pid: 2954 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107
__down_write_common kernel/locking/rwsem.c:1262 [inline]
__down_write_common kernel/locking/rwsem.c:1259 [inline]
__down_write kernel/locking/rwsem.c:1271 [inline]
down_write+0x137/0x150 kernel/locking/rwsem.c:1518
usb_register_dev drivers/usb/core/file.c:187 [inline]
usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
sisusb_probe+0x21c/0xbe3 drivers/usb/misc/sisusbvga/sisusb.c:3039
usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_set_configuration+0x113f/0x1910 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
hub_port_connect drivers/usb/core/hub.c:5348 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5488 [inline]
port_event drivers/usb/core/hub.c:5634 [inline]
hub_event+0x2357/0x4330 drivers/usb/core/hub.c:5716
process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INFO: task kworker/1:5:6907 blocked for more than 144 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5 state:D stack:25424 pid: 6907 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107
__down_write_common kernel/locking/rwsem.c:1262 [inline]
__down_write_common kernel/locking/rwsem.c:1259 [inline]
__down_write kernel/locking/rwsem.c:1271 [inline]
down_write+0x137/0x150 kernel/locking/rwsem.c:1518
usb_register_dev drivers/usb/core/file.c:187 [inline]
usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
sisusb_probe+0x21c/0xbe3 drivers/usb/misc/sisusbvga/sisusb.c:3039
usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_set_configuration+0x113f/0x1910 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
hub_port_connect drivers/usb/core/hub.c:5348 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5488 [inline]
port_event drivers/usb/core/hub.c:5634 [inline]
hub_event+0x2357/0x4330 drivers/usb/core/hub.c:5716
process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INFO: task kworker/1:6:9012 blocked for more than 144 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:6 state:D stack:24672 pid: 9012 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1107
__down_write_common kernel/locking/rwsem.c:1262 [inline]
__down_write_common kernel/locking/rwsem.c:1259 [inline]
__down_write kernel/locking/rwsem.c:1271 [inline]
down_write+0x137/0x150 kernel/locking/rwsem.c:1518
usb_register_dev drivers/usb/core/file.c:187 [inline]
usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
sisusb_probe+0x21c/0xbe3 drivers/usb/misc/sisusbvga/sisusb.c:3039
usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_set_configuration+0x113f/0x1910 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
call_driver_probe drivers/base/dd.c:517 [inline]
really_probe+0x245/0xcc0 drivers/base/dd.c:596
__driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
__device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
__device_attach+0x228/0x4a0 drivers/base/dd.c:969
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
device_add+0xc17/0x1ee0 drivers/base/core.c:3396
usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
hub_port_connect drivers/usb/core/hub.c:5348 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5488 [inline]
port_event drivers/usb/core/hub.c:5634 [inline]
hub_event+0x2357/0x4330 drivers/usb/core/hub.c:5716
process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INFO: task syz-executor.4:10534 blocked for more than 145 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:28496 pid:10534 ppid: 7078 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425
__mutex_lock_common kernel/locking/mutex.c:669 [inline]
__mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729
sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2397
usb_open+0x204/0x2e0 drivers/usb/core/file.c:48
chrdev_open+0x266/0x770 fs/char_dev.c:414
do_dentry_open+0x4c8/0x11d0 fs/open.c:822
do_open fs/namei.c:3428 [inline]
path_openat+0x1c9a/0x2740 fs/namei.c:3561
do_filp_open+0x1aa/0x400 fs/namei.c:3588
do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
do_sys_open fs/open.c:1216 [inline]
__do_sys_openat fs/open.c:1232 [inline]
__se_sys_openat fs/open.c:1227 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f8e09790954
RSP: 002b:00007f8e08f52cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8e098e0f60 RCX: 00007f8e09790954
RDX: 0000000000000002 RSI: 00007f8e08f52d60 RDI: 00000000ffffff9c
RBP: 00007f8e08f52d60 R08: 0000000000000000 R09: 000000000000000f
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffd411b841f R14: 00007f8e08f53300 R15: 0000000000022000
INFO: task syz-executor.3:10535 blocked for more than 145 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:27888 pid:10535 ppid: 7075 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425
__mutex_lock_common kernel/locking/mutex.c:669 [inline]
__mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729
sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2397
usb_open+0x204/0x2e0 drivers/usb/core/file.c:48
chrdev_open+0x266/0x770 fs/char_dev.c:414
do_dentry_open+0x4c8/0x11d0 fs/open.c:822
do_open fs/namei.c:3428 [inline]
path_openat+0x1c9a/0x2740 fs/namei.c:3561
do_filp_open+0x1aa/0x400 fs/namei.c:3588
do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
do_sys_open fs/open.c:1216 [inline]
__do_sys_openat fs/open.c:1232 [inline]
__se_sys_openat fs/open.c:1227 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fbada0b6954
RSP: 002b:00007fbad9878cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fbada206f60 RCX: 00007fbada0b6954
RDX: 0000000000000002 RSI: 00007fbad9878d60 RDI: 00000000ffffff9c
RBP: 00007fbad9878d60 R08: 0000000000000000 R09: 000000000000000f
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffdb0deb55f R14: 00007fbad9879300 R15: 0000000000022000
INFO: task syz-executor.1:10559 blocked for more than 146 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:28496 pid:10559 ppid: 7076 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_read_slowpath+0x4c5/0x990 kernel/locking/rwsem.c:993
__down_read_common kernel/locking/rwsem.c:1214 [inline]
__down_read kernel/locking/rwsem.c:1223 [inline]
down_read+0xe4/0x440 kernel/locking/rwsem.c:1466
usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
chrdev_open+0x266/0x770 fs/char_dev.c:414
do_dentry_open+0x4c8/0x11d0 fs/open.c:822
do_open fs/namei.c:3428 [inline]
path_openat+0x1c9a/0x2740 fs/namei.c:3561
do_filp_open+0x1aa/0x400 fs/namei.c:3588
do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
do_sys_open fs/open.c:1216 [inline]
__do_sys_openat fs/open.c:1232 [inline]
__se_sys_openat fs/open.c:1227 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f1dc0353954
RSP: 002b:00007f1dbfb15cc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1dc04a3f60 RCX: 00007f1dc0353954
RDX: 0000000000000002 RSI: 00007f1dbfb15d60 RDI: 00000000ffffff9c
RBP: 00007f1dbfb15d60 R08: 0000000000000000 R09: 000000000000000f
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffcd4e8c98f R14: 00007f1dbfb16300 R15: 0000000000022000
INFO: task syz-executor.0:10560 blocked for more than 146 seconds.
Not tainted 5.15.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:28496 pid:10560 ppid: 7074 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:4940 [inline]
__schedule+0xb44/0x5960 kernel/sched/core.c:6287
schedule+0xd3/0x270 kernel/sched/core.c:6366
rwsem_down_read_slowpath+0x4c5/0x990 kernel/locking/rwsem.c:993
__down_read_common kernel/locking/rwsem.c:1214 [inline]
__down_read kernel/locking/rwsem.c:1223 [inline]
down_read+0xe4/0x440 kernel/locking/rwsem.c:1466
usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
chrdev_open+0x266/0x770 fs/char_dev.c:414
do_dentry_open+0x4c8/0x11d0 fs/open.c:822
do_open fs/namei.c:3428 [inline]
path_openat+0x1c9a/0x2740 fs/namei.c:3561
do_filp_open+0x1aa/0x400 fs/namei.c:3588
do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
do_sys_open fs/open.c:1216 [inline]
__do_sys_openat fs/open.c:1232 [inline]
__se_sys_openat fs/open.c:1227 [inline]
__x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f0dc353d954
RSP: 002b:00007f0dc2cffcc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0dc368df60 RCX: 00007f0dc353d954
RDX: 0000000000000002 RSI: 00007f0dc2cffd60 RDI: 00000000ffffff9c
RBP: 00007f0dc2cffd60 R08: 0000000000000000 R09: 000000000000000f
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffc98eb74cf R14: 00007f0dc2d00300 R15: 0000000000022000
Showing all locks held in the system:
1 lock held by ksoftirqd/1/19:
#0: ffff8880b9d31a58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:474
6 locks held by kworker/1:0/20:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc90000da7db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146d07220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146d07220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff88814845f220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88814845f220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff8880771131a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff8880771131a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
1 lock held by khungtaskd/27:
#0: ffffffff8b981b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
6 locks held by kworker/1:2/1056:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc90004ca7db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146c0f220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146c0f220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff88807525c220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88807525c220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff888024f921a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff888024f921a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
6 locks held by kworker/0:3/2954:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc90002c9fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146c97220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146c97220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff888077575220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff888077575220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff88806a74c1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff88806a74c1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
1 lock held by in:imklog/6479:
6 locks held by kworker/1:4/6906:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc90005887db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146c3f220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146c3f220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff88807aa83220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88807aa83220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff88807a1751a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff88807a1751a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
6 locks held by kworker/1:5/6907:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc90005867db0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146caf220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146caf220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff88814845d220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88814845d220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff8880787151a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff8880787151a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
6 locks held by kworker/1:6/9012:
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
#0: ffff888016142938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
#1: ffffc9000d08fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
#2: ffff888146d17220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888146d17220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4330 drivers/usb/core/hub.c:5662
#3: ffff88814845e220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88814845e220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#4: ffff88801b1c51a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff88801b1c51a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev drivers/usb/core/file.c:187 [inline]
#5: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_register_dev+0x19d/0x7e0 drivers/usb/core/file.c:156
2 locks held by kworker/u4:6/9127:
2 locks held by syz-executor.5/10523:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
#1: ffff8880183080d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2397
2 locks held by syz-executor.4/10534:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
#1: ffff8880183080d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2397
2 locks held by syz-executor.3/10535:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
#1: ffff8880183080d0 (&(sisusb->lock)){+.+.}-{3:3}, at: sisusb_open+0xb2/0x4d0 drivers/usb/misc/sisusbvga/sisusb.c:2397
1 lock held by syz-executor.1/10559:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
1 lock held by syz-executor.0/10560:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
1 lock held by syz-executor.2/10975:
#0: ffffffff8c81f970 (minor_rwsem#2){++++}-{3:3}, at: usb_open+0x24/0x2e0 drivers/usb/core/file.c:39
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__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:105
nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xc1d/0xf50 kernel/hung_task.c:295
kthread+0x3e5/0x4d0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2958 Comm: systemd-journal Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:security_file_free+0x36/0xd0 security/security.c:1529
Code: 00 fc ff df 53 e8 da a8 d7 fd 48 8b 1d 5b 7a 94 07 48 85 db 74 31 e8 c9 a8 d7 fd 48 8d 7b 18 48 89 f8 48 c1 e8 03 80 3c 28 00 <75> 75 4c 89 e7 ff 53 18 48 89 d8 48 c1 e8 03 80 3c 28 00 75 69 48
RSP: 0018:ffffc900014dfe40 EFLAGS: 00000246
RAX: 1ffffffff1667990 RBX: ffffffff8b33cc68 RCX: 0000000000000000
RDX: ffff88807b668000 RSI: ffffffff839f2f57 RDI: ffffffff8b33cc80
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff888010db4ab3
R10: ffffffff83a75159 R11: 0000000000000000 R12: ffff888026673680
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007fca341728c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fca3163f018 CR3: 000000001b9ac000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
file_free fs/file_table.c:55 [inline]
__fput+0x3d8/0x9f0 fs/file_table.c:298
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fca33701840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffdd68dba78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: fffffffffffffffe RBX: 00007ffdd68dbd80 RCX: 00007fca33701840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005653db47ec10
RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00005653db472040 R14: 00007ffdd68dbd40 R15: 00005653db47e270
----------------
Code disassembly (best guess), 3 bytes skipped:
0: df 53 e8 fists -0x18(%rbx)
3: da a8 d7 fd 48 8b fisubrl -0x74b70229(%rax)
9: 1d 5b 7a 94 07 sbb $0x7947a5b,%eax
e: 48 85 db test %rbx,%rbx
11: 74 31 je 0x44
13: e8 c9 a8 d7 fd callq 0xfdd7a8e1
18: 48 8d 7b 18 lea 0x18(%rbx),%rdi
1c: 48 89 f8 mov %rdi,%rax
1f: 48 c1 e8 03 shr $0x3,%rax
23: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1)
* 27: 75 75 jne 0x9e <-- trapping instruction
29: 4c 89 e7 mov %r12,%rdi
2c: ff 53 18 callq *0x18(%rbx)
2f: 48 89 d8 mov %rbx,%rax
32: 48 c1 e8 03 shr $0x3,%rax
36: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1)
3a: 75 69 jne 0xa5
3c: 48 rex.W
Tested on:
commit: 2f111a6f Merge tag 'ceph-for-5.15-rc7' of git://github..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
console output: https://syzkaller.appspot.com/x/log.txt?x=179ee8d2b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=61f4d9af07d3bbdf
dashboard link: https://syzkaller.appspot.com/bug?extid=fd9d03311cdce9a9ec36
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=1245f39cb00000
prev parent reply other threads:[~2021-10-27 12:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-06 15:22 INFO: task hung in sisusb_open syzbot
2021-10-22 15:10 ` [syzbot] " syzbot
2021-10-25 14:40 ` Oliver Neukum
2021-10-27 6:27 ` Dmitry Vyukov
2021-10-27 9:52 ` Oliver Neukum
2021-10-27 12:28 ` syzbot [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0000000000006405cf05cf54bacb@google.com \
--to=syzbot+fd9d03311cdce9a9ec36@syzkaller.appspotmail.com \
--cc=andreyknvl@google.com \
--cc=linux-usb@vger.kernel.org \
--cc=oneukum@suse.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=thomas@winischhofer.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.