Re: INFO: task hung in devtmpfs_submit_req

From: Greg Kroah-Hartman
Date: Tue Jan 11 2022 - 02:33:32 EST


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