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Date: Fri, 31 May 2024 13:14:17 -0400
From: =?utf-8?B?TsOtY29sYXMgRi4gUi4gQS4=?= Prado <nfraprado@collabora.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Mark Brown <broonie@kernel.org>, linux-spi@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Neil Armstrong <neil.armstrong@linaro.org>
Subject: Re: [PATCH v1 0/2] spi: Make dummy SG handling robust
Message-ID: <3f0606f3-c781-49e1-a946-dc9aea77f835@notapiano>
References: <20240531094658.1598969-1-andy.shevchenko@gmail.com>
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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@gmail.com> wrote:
> > On Fri, May 31, 2024 at 5:37 PM Nícolas F. R. A. Prado
> > <nfraprado@collabora.com> 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