Re: [RFT PATCH v2] xhci: process isoc TD properly when there was an error mid TD.

["Michał Pecio" <michal.pecio@gmail.com>]

My usual set of tests passes:
- no spam on disconnection from NEC
- no stream lockup on random errors on NEC
- no spam on disconnection from VIA
- finish_td called with right frame->status on VIA
  (checked by means of extra printks)

> +		/* Error mid TD, don't give TD back yet */
> +		td->error_mid_td = true;
> +		td->urb_length_set = true;
> +
> +		frame->actual_length = sum_trb_lengths(xhci, ep->ring, ep_trb) +
> +			ep_trb_len - remaining;
Not a problem with this patch, but I noticed that every single use of
this function ends up adding ep_trb_len, maybe it could be inclusive.

> +		td->urb->actual_length += frame->actual_length;
In your first email you mentioned hosts responding to every single TRB,
perhaps with the same error code repeated each time?

I imagine it could be problematic here if such hosts really exist and
if there are enough TRBs to execute this line twice. A check for the
error_mid_td bit previously set could help, if this is a real risk.


Thanks,
Michal