Re: [PATCH v4] media: verisilicon: Fix kernel panic due to __initconst misuse

[Francesco Dolcini]

On Mon, Mar 16, 2026 at 11:25:53AM -0400, Nicolas Dufresne wrote:
> Le jeudi 12 mars 2026 à 18:34 +0100, Francesco Dolcini a écrit :
> > Hello,
> > 
> > On Fri, Mar 06, 2026 at 11:10:57AM +0800, ming.qian@xxxxxxxxxxx wrote:
> > > From: Ming Qian <ming.qian@xxxxxxxxxxx>
> > > 
> > > Fix a kernel panic when probing the driver as a module:
> > > 
> > >   Unable to handle kernel paging request at virtual address
> > >   ffffd9c18eb05000
> > >   of_find_matching_node_and_match+0x5c/0x1a0
> > >   hantro_probe+0x2f4/0x7d0 [hantro_vpu]
> > > 
> > > The imx8mq_vpu_shared_resources array is referenced by variant
> > > structures through their shared_devices field. When built as a
> > > module, __initconst causes this data to be freed after module
> > > init, but it's later accessed during probe, causing a page fault.
> > > 
> > > The imx8mq_vpu_shared_resources is referenced from non-init code,
> > > so keeping __initconst or __initconst_or_module here is wrong.
> > > 
> > > Drop the __initconst annotation and let it live in the normal .rodata
> > > section.
> > > 
> > > A bug of __initconst called from regular non-init probe code
> > > leading to bugs during probe deferrals or during unbind-bind cycles.
> > > 
> > > Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> > > Closes: https://lore.kernel.org/all/68ef934f-baa0-4bf6-93d8-834bbc441e66@xxxxxxxxxx/
> > > Reported-by: Franz Schnyder <franz.schnyder@xxxxxxxxxxx>
> > > Closes: https://lore.kernel.org/all/n3qmcb62tepxltoskpf7ws6yiirc2so62ia23b42rj3wlmpl67@rvkbuirx7kkp/
> > > Fixes: e0203ddf9af7 ("media: verisilicon: Avoid G2 bus error while decoding H.264 and HEVC")
> > > Suggested-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> > > Suggested-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > > Reviewed-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > > Signed-off-by: Ming Qian <ming.qian@xxxxxxxxxxx>
> > 
> > What's the plan to merge this? It fixes a quite severe regression,
> > a boot failure.
> 
> To be decided this week. The commit message does not say if it was released, or
> came in RCs (and I didn't check myself yet). I'd say, if its the first one, it
> will go through next and backports, otherwise its is really tight to get that
> into the RC series, but serious enough. Please fill the gap if you have time,
> and I'll handle it later, probably tomorrow.

This fixes commit e0203ddf9af7 ("media: verisilicon: Avoid G2 bus error
while decoding H.264 and HEVC"), that was merged in 7.0-rc1.

As of now, because of that, 7.0-rc is not booting on affected platforms
(i.MX8MP), to me this needs to get merged before 7.0 is released.

Francesco