On Mon Jan 26, 2026 at 9:47 AM CET, Liu Ying wrote:
>
>
> On Mon, Jan 26, 2026 at 09:33:38AM +0100, Luca Ceresoli wrote:
>> On Fri Jan 23, 2026 at 10:22 AM CET, Liu Ying wrote:
>>> In case the channel0 is unavailable and bailing out from free_child is
>>> needed when we fail to add a DRM bridge for the available channel1,
>>> pointer pc->ch[0] in the bailout path would be NULL and it would be
>>> dereferenced as pc->ch[0]->bridge.next_bridge. Fix this by checking
>>> pc->ch[0] before dereferencing it.
>>
>> Thanks for checking this code and providing fixes! These drivers have a
>> complex code path so I had a hard time in following the logic without neing
>> able to test on hardware. Apologies for the issues emerged.
>
> Thanks for your quick review and hard work!
>
>>
>>> Fixes: ae754f049ce1 ("drm/bridge: imx8qxp-pixel-combiner: get/put the next
>>> bridge")
>>> Fixes: 99764593528f ("drm/bridge: imx8qxp-pixel-combiner: convert to
>>> devm_drm_bridge_alloc() API")
>>
>> The bug was introduced by 99764593528f, while ae754f049ce1 is not changing
>> the bug, so for the sake of precision we can remove the first 'Fixes:'
>> line.
>
> I added Fixes tag for ae754f049ce1 because it is the first commit which
> this commit could be applied upon properly. Maybe this helps some tools
> apply this commit or maybe tools are smart enough to find ae754f049ce1
> automatically?
Uhm, good point, maybe it can be a useful reference for the stable team to
backport the fix... Well, let's leave both lines then:
Reviewed-by: Luca Ceresoli <[email protected]>
I'm applying this series perhaps tomorrow (if no one does it before).
Luca
--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
