RE: [PATCH] usb: dwc3: gadget: don't remove the request if bus-expired

From: Zengtao (B)
Date: Mon Jan 21 2019 - 04:34:29 EST


Hi balbi:

>-----Original Message-----
>From: Felipe Balbi [mailto:felipe.balbi@xxxxxxxxxxxxxxx]
>Sent: Monday, January 14, 2019 4:13 PM
>To: Zengtao (B) <prime.zeng@xxxxxxxxxxxxx>
>Cc: Zengtao (B) <prime.zeng@xxxxxxxxxxxxx>; Greg Kroah-Hartman
><gregkh@xxxxxxxxxxxxxxxxxxx>; linux-usb@xxxxxxxxxxxxxxx;
>linux-kernel@xxxxxxxxxxxxxxx
>Subject: Re: [PATCH] usb: dwc3: gadget: don't remove the request if
>bus-expired
>
>* PGP Signed by an unknown key
>
>
>Hi,
>
>Zeng Tao <prime.zeng@xxxxxxxxxxxxx> writes:
>> We have already returned EAGAIN for bus-expiry, and it's designed to
>> start with a future Frame number and start the transfer again. So we
>> should not remove the request for that case.
>>
>> Signed-off-by: Zeng Tao <prime.zeng@xxxxxxxxxxxxx>
>
>Do we need a Fixes tag here? How about Cc stable? Can you share
>tracepoints exposing the problem?
>

I am not sure that we need to Fixes tag, it's not related to any single patch, but
there is definitely something wrong, after rethinking it again, I found that there
are still some problems for this patch, for the reties inside the driver, we should not
remove the request, but if we return -EAGAIN to the gadget layer, we should because
the gadget will requeue the request again if we return -EAGAIN.

Any suggestions.

>
>thanks
>
>--
>balbi
>
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