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

From: Nícolas F. R. A. Prado
Date: Fri May 31 2024 - 13:14:31 EST


On Fri, May 31, 2024 at 06:51:46PM +0300, Andy Shevchenko wrote:
> On Fri, May 31, 2024 at 6:46 PM Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> wrote:
> > 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:
>
> ...
>
> > > 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?
>
> Ah, you wrote "either", so it seems you have tried that already.

Yes exactly. Both patches are troublesome. Patch 2 causes a slightly different
null pointer dereference, in "dcache_clean_poc+0x20/0x38", as the stack trace I
posted shows.

Thanks,
Nícolas