Re: INFO: task hung in devtmpfs_submit_req

[Greg Kroah-Hartman]

On Tue, Jan 11, 2022 at 10:41:06AM +0800, cruise k wrote:
> Hi,
> 
> Syzkaller found the following issue:
> 
> HEAD commit: 75acfdb Linux 5.16-rc8
> git tree: upstream
> console output: https://pastebin.com/raw/gwHBn2EB
> kernel config: https://pastebin.com/raw/XsnKfdRt
> 
> And hope the report log can help you.
> 
> INFO: task kworker/6:4:13959 blocked for more than 145 seconds.
>       Not tainted 5.16.0-rc8+ #10
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:kworker/6:4     state:D stack:26944 pid:13959 ppid:     2 flags:0x00004000
> Workqueue: usb_hub_wq hub_event
> Call Trace:
>  <TASK>
>  __schedule+0xcd9/0x2550
>  schedule+0xd2/0x260
>  schedule_timeout+0x5e5/0x890
>  wait_for_completion+0x17b/0x280
>  devtmpfs_submit_req+0xa8/0x100
>  devtmpfs_delete_node+0xe1/0x150
>  device_del+0xadf/0xe80
>  usb_disconnect+0x4a4/0x8c0
>  hub_event+0x199c/0x4090
>  process_one_work+0x9df/0x16a0
>  worker_thread+0x90/0xe20
>  kthread+0x405/0x4f0
>  ret_from_fork+0x1f/0x30
>  </TASK>

Wonderful, please submit a change to resolve this issue.

thanks,

greg k-h