Re: [syzbot] [usb?] INFO: task hung in usb_port_suspend

From: Alan Stern
Date: Fri Oct 11 2024 - 10:08:32 EST


On Fri, Oct 11, 2024 at 06:08:30AM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 4a9fe2a8ac53 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=17d067d0580000
> 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
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1312c327980000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/883c5319cb52/disk-4a9fe2a8.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/caf4421ed2ef/vmlinux-4a9fe2a8.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/d8e3beb01d49/bzImage-4a9fe2a8.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+f342ea16c9d06d80b585@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> INFO: task kworker/1:0:24 blocked for more than 143 seconds.
> Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53 #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:kworker/1:0 state:D stack:23808 pid:24 tgid:24 ppid:2 flags:0x00004000
> Workqueue: pm pm_runtime_work

Let's try to verify that this problem really was caused by the timer
changes to dummy-hcd. The following commit is the one preceding those
changes.

#syz test: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git 920e7522e3ba

Alan Stern