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

From: Pawel Laszczak
Date: Fri Jul 14 2023 - 04:59:05 EST


>
>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?
>
>> 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.

Thank,
Pawel

>
>
>> if (!pep->endpoint.desc) {
>> dev_err(pdev->dev,
>> "%s: can't dequeue to disabled endpoint\n",
>> --
>> 2.37.2
>>
>
>--
>
>Thanks,
>Peter Chen