Re: [PATCH] usb: cdnsp: Fixes issue with dequeuing not queued requests

From: Peter Chen
Date: Sun Jul 16 2023 - 07:55:59 EST


On 23-07-14 07:19:21, Pawel Laszczak wrote:
> >
> >On 23-07-13 04:14:29, Pawel Laszczak wrote:
> >> Gadget ACM while unloading module try to dequeue not queued usb
> >> request which causes the kernel to crash.
> >> Patch adds extra condition to check whether usb request is processed
> >> by CDNSP driver.
> >>
> >
> >Why ACM does that?

Would you please explain which situation triggers it?

> >
> >> cc: <stable@xxxxxxxxxxxxxxx>
> >> Fixes: 3d82904559f4 ("usb: cdnsp: cdns3 Add main part of Cadence
> >> USBSSP DRD Driver")
> >> Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
> >> ---
> >> drivers/usb/cdns3/cdnsp-gadget.c | 3 +++
> >> 1 file changed, 3 insertions(+)
> >>
> >> diff --git a/drivers/usb/cdns3/cdnsp-gadget.c
> >> b/drivers/usb/cdns3/cdnsp-gadget.c
> >> index fff9ec9c391f..3a30c2af0c00 100644
> >> --- a/drivers/usb/cdns3/cdnsp-gadget.c
> >> +++ b/drivers/usb/cdns3/cdnsp-gadget.c
> >> @@ -1125,6 +1125,9 @@ static int cdnsp_gadget_ep_dequeue(struct
> >usb_ep *ep,
> >> unsigned long flags;
> >> int ret;
> >>
> >> + if (request->status != -EINPROGRESS)
> >> + return 0;
> >> +
> >
> >Why not you use pending list which used at cdnsp_ep_enqueue to do this?
>
> It's just simpler and faster way - no other reasons.

Okay, get it.

--

Thanks,
Peter Chen