syzbot


INFO: task hung in kernfs_remove

Status: auto-obsoleted due to no activity on 2024/08/29 15:31
Subsystems: kernfs
[Documentation on labels]
First crash: 293d, last: 292d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in kernfs_remove 1 1950d 1950d 0/1 auto-closed as invalid on 2020/03/15 06:19
android-414 INFO: task hung in kernfs_remove 1 2207d 2166d 0/1 auto-closed as invalid on 2019/08/31 16:46
upstream INFO: task hung in kernfs_remove (2) kernfs 2 168d 179d 0/28 auto-obsoleted due to no activity on 2024/12/31 03:21

Sample crash report:
INFO: task kworker/0:2:929 blocked for more than 143 seconds.
      Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2     state:D
 stack:21624 pid:929   tgid:929   ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event

Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
 kernfs_remove+0x72/0xa0 fs/kernfs/dir.c:1527
 __kobject_del+0xe2/0x310 lib/kobject.c:604
 kobject_del+0x45/0x60 lib/kobject.c:627
 device_del+0x7ff/0x9b0 drivers/base/core.c:3930
 usb_disable_device+0x3bf/0x850 drivers/usb/core/message.c:1418
 usb_disconnect+0x340/0x950 drivers/usb/core/hub.c:2304
 hub_port_connect drivers/usb/core/hub.c:5361 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
 port_event drivers/usb/core/hub.c:5821 [inline]
 hub_event+0x1eb9/0x5150 drivers/usb/core/hub.c:5903
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task udevd:4543 blocked for more than 144 seconds.
      Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D
 stack:23568 pid:4543  tgid:4543  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
 rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
 __down_read_common kernel/locking/rwsem.c:1250 [inline]
 __down_read kernel/locking/rwsem.c:1263 [inline]
 down_read+0x705/0xa40 kernel/locking/rwsem.c:1528

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/30 05:20 upstream 4a4be1ad3a6e 34889ee3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in kernfs_remove
2024/05/31 15:23 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 1613e604df0c 0c378259 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: task hung in kernfs_remove
* Struck through repros no longer work on HEAD.