Re: [PATCH v1 0/2] spi: Make dummy SG handling robust

From: Andy Shevchenko
Date: Fri May 31 2024 - 11:47:08 EST


On Fri, May 31, 2024 at 5:37 PM Nícolas F. R. A. Prado
<nfraprado@xxxxxxxxxxxxx> wrote:
> On Fri, May 31, 2024 at 12:44:31PM +0300, Andy Shevchenko wrote:
> > There's an unreliable code to handle DMA mappings on unidirection transfers.
> > This series does two things:
> > - it reverts the seemingly unnecessary change
> > - it reworks dummy SG list handling
> >
> > There is no need to backport that AFAIU, but no harm to apply for v6.10 aka
> > the current release cycle. Guys, please test these.
> >
> > Andy Shevchenko (2):
> > spi: Revert "Check if transfer is mapped before calling DMA sync APIs"
> > spi: Do not rely on the SG table and respective API implementations

> Hi Andy,
>
> applying either of these patches causes issues. See the traces for each one
> below. This was tested on top of next-20240531, which works fine.

Oh, thank you very much for prompt testing! Can you test just the
second one without the revert?

So, your patch seems needed for the sync API calls, while I considered
only mapping APIs.

--
With Best Regards,
Andy Shevchenko