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Date:   Wed, 27 Sep 2023 13:47:38 -0700
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Subject: Re: [PATCH v1 0/2] usb: gadget: uvc: stability fixes when stopping
 streams
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From:   Avichal Rakesh <arakesh@google.com>
To:     Michael Grzeschik <mgr@pengutronix.de>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Daniel Scally <dan.scally@ideasonboard.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230912041910.726442-1-arakesh@google.com>
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On 9/19/23 11:24, Avichal Rakesh wrote:
> 
> 
> On 9/15/23 18:35, Avichal Rakesh wrote:
>>
>>
>> On 9/15/23 16:16, Michael Grzeschik wrote:
>>> Hi Avichal
>>>
>>> On Thu, Sep 14, 2023 at 04:05:36PM -0700, Avichal Rakesh wrote:
>>>> On Mon, Sep 11, 2023 at 9:19 PM Avichal Rakesh <arakesh@google.com> wrote:
>>>>>
>>>>> We have been seeing two main bugs when stopping stream:
>>>>> 1. attempting to queue usb_requests on a disabled usb endpoint, and
>>>>> 2. use-after-free problems for inflight requests
>>>>>

>>>
>>> The error path triggering these list errors are usually in the
>>> dwc3 driver handling the cancelled or completed list.
>>
>> It looks like we're still freeing un-returned requests :(. If you still have
>> the setup can you pull the uvc logs to see if waiting for requests to be returned timed 
>> out? I wonder if dwc3's interrupt handler is being scheduled too late. 500ms seemed
>> like a reasonable time out to me, but this seems to prove otherwise.
>>
> 
> 
> Hey Michael, were you able to look into the comments from the previous
> email? 
> 

Bumping the thread up. Laurent, Dan, and Michael: the patches are ready to
review/test. Please take a look when possible. 

Thank you!
Avi.