Re: [PATCH v1] media: camss: vfe: Don't use vfe->base before it's assigned

From: Robert Foss
Date: Wed Aug 11 2021 - 09:42:28 EST


On Wed, 11 Aug 2021 at 11:41, Robert Foss <robert.foss@xxxxxxxxxx> wrote:
>
> Hey Marek,
>
> Thanks for testing this.
>
> On Wed, 11 Aug 2021 at 09:48, Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote:
> >
> > On 10.08.2021 12:33, Robert Foss wrote:
> > > vfe->ops->hw_version(vfe) being called before vfe->base has been assigned
> > > is incorrect and causes crashes.
> > >
> > > Fixes: b10b5334528a9 ("media: camss: vfe: Don't read hardware version needlessly")
> > >
> > > Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
> > > Signed-off-by: Robert Foss <robert.foss@xxxxxxxxxx>
> >
> > With this patch applied on top of linux next-20210810 instead of the
> > NULL pointer dereference I get following error on DragonBoard410c while
> > loading kernel modules:
> >
> > [ 18.480608] qcom-venus 1d00000.video-codec: Adding to iommu group 1
> > [ 18.536167] qcom-camss 1b0ac00.camss: Adding to iommu group 2
> > [ 18.600373] Internal error: synchronous external abort: 96000010 [#1]
> > PREEMPT SMP
>

After testing this patch + linux-next[1] I'm not able to replicate the
'Internal error' above on the db410c. And I don't think it is related
to this patch.

Are you seeing the same error on [1]? And are you seeing it before the
b10b5334528a9 ("media: camss: vfe: Don't read hardware version
needlessly") patch?

[1] https://git.linaro.org/people/robert.foss/linux.git/log/?h=camss_print_fix_v1


Rob