[PATCH 0/3] drm/bridge: imx: A few fixes

Liu Ying posted 3 patches 2 weeks, 2 days ago
drivers/gpu/drm/bridge/imx/imx8qxp-ldb.c            | 7 +++++--
drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 2 +-
drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c        | 3 +++
3 files changed, 9 insertions(+), 3 deletions(-)
[PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Liu Ying 2 weeks, 2 days ago
Hi,

This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
Each patch fixes a NULL pointer dereference issue and stands alone.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
Liu Ying (3):
      drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
      drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
      drm/bridge: imx8qxp-pixel-combiner: Fix bailout for imx8qxp_pc_bridge_probe()

 drivers/gpu/drm/bridge/imx/imx8qxp-ldb.c            | 7 +++++--
 drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 2 +-
 drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c        | 3 +++
 3 files changed, 9 insertions(+), 3 deletions(-)
---
base-commit: e3b32dcb9f23e3c3927ef3eec6a5842a988fb574
change-id: 20260122-imx8qxp-drm-bridge-fixes-dc7cb2564506

Best regards,
-- 
Liu Ying <victor.liu@nxp.com>
Re: [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Luca Ceresoli 5 days, 4 hours ago
On Fri, 23 Jan 2026 17:22:14 +0800, Liu Ying wrote:
> This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
> Each patch fixes a NULL pointer dereference issue and stands alone.
> 
> 

Applied, thanks!

[1/3] drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
      (no commit info)
[2/3] drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
      (no commit info)
[3/3] drm/bridge: imx8qxp-pixel-combiner: Fix bailout for imx8qxp_pc_bridge_probe()
      commit: fe6d29b082d49df336ebb92226a3c004ae9e3222

Best regards,
-- 
Luca Ceresoli <luca.ceresoli@bootlin.com>
Re: (subset) [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Luca Ceresoli 1 week, 5 days ago
On Fri, 23 Jan 2026 17:22:14 +0800, Liu Ying wrote:
> This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
> Each patch fixes a NULL pointer dereference issue and stands alone.
> 
> 

Applied, thanks!

[1/3] drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
      commit: 852c68bf42965ee38b465d2d6f7b965eb0b5dc1d
[2/3] drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
      commit: db7e7ea838c916ee4cdf26bee126fd36f58295dc

Best regards,
-- 
Luca Ceresoli <luca.ceresoli@bootlin.com>
Re: (subset) [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Liu Ying 1 week, 4 days ago
Hi Luca,

On Tue, Jan 27, 2026 at 12:35:47PM +0100, Luca Ceresoli wrote:
> 
> On Fri, 23 Jan 2026 17:22:14 +0800, Liu Ying wrote:
>> This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
>> Each patch fixes a NULL pointer dereference issue and stands alone.
>>
>>
> 
> Applied, thanks!
> 
> [1/3] drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
>       commit: 852c68bf42965ee38b465d2d6f7b965eb0b5dc1d
> [2/3] drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
>       commit: db7e7ea838c916ee4cdf26bee126fd36f58295dc

Any reason why patch 3/3 is not applied?

> 
> Best regards,

-- 
Regards,
Liu Ying
Re: (subset) [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Luca Ceresoli 1 week, 4 days ago
Hello Liu,

On Wed Jan 28, 2026 at 2:50 AM CET, Liu Ying wrote:
> Hi Luca,
>
> On Tue, Jan 27, 2026 at 12:35:47PM +0100, Luca Ceresoli wrote:
>>
>> On Fri, 23 Jan 2026 17:22:14 +0800, Liu Ying wrote:
>>> This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
>>> Each patch fixes a NULL pointer dereference issue and stands alone.
>>>
>>>
>>
>> Applied, thanks!
>>
>> [1/3] drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
>>       commit: 852c68bf42965ee38b465d2d6f7b965eb0b5dc1d
>> [2/3] drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
>>       commit: db7e7ea838c916ee4cdf26bee126fd36f58295dc
>
> Any reason why patch 3/3 is not applied?

Yes, the reason is there's a patch conflict and I still have to find out
how to handle it.

Patch 3 by the rules [0] should go to drm-misc-fixes because the bug (added
by [1]) is already on Linus' master tree (since v6.17), but it does not
apply there due to a conflict with an unrelated change [2] currently on
drm-misc-next.

Note that [1] and [2] are the two commits mentioned in your 'Fixes: 'tags.

I had a chat with Maxime on #dir-devel about how to handle this situation
but still haven't got a final answer.

I guess the correct way is:

 1. apply patch 3 on drm-misc-next, where it applies cleanly
 2. send a modified patch for drm-misc-fixes, to fix ASAP the master branch

Would you send the patch as in item 2, so it can be applied to
drm-misc-fixes and have master fixed ASAP? Note iit should not mention [2]
in the Fixes: tag because [2] is not yet on master. I can send it of course
but you can test on hardware so that would be the best option (and I'm a
bit overloaded at the moment).

[0] https://drm.pages.freedesktop.org/maintainer-tools/committer/committer-drm-misc.html
[1] commit 99764593528f ("drm/bridge: imx8qxp-pixel-combiner: convert to devm_drm_bridge_alloc() API")
[2] commit ae754f049ce1 ("drm/bridge: imx8qxp-pixel-combiner: get/put the next bridge")

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
Re: (subset) [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Liu Ying 1 week, 3 days ago

On Wed, Jan 28, 2026 at 04:26:22PM +0100, Luca Ceresoli wrote:
> Hello Liu,

Hello Luca,

> 
> On Wed Jan 28, 2026 at 2:50 AM CET, Liu Ying wrote:
>> Hi Luca,
>>
>> On Tue, Jan 27, 2026 at 12:35:47PM +0100, Luca Ceresoli wrote:
>>>
>>> On Fri, 23 Jan 2026 17:22:14 +0800, Liu Ying wrote:
>>>> This patch series contains 3 bug fixes for i.MX8QXP DRM bridges.
>>>> Each patch fixes a NULL pointer dereference issue and stands alone.
>>>>
>>>>
>>>
>>> Applied, thanks!
>>>
>>> [1/3] drm/bridge: imx8qxp-ldb: Fix NULL pointer dereference in imx8qxp_ldb_bridge_destroy()
>>>       commit: 852c68bf42965ee38b465d2d6f7b965eb0b5dc1d
>>> [2/3] drm/bridge: imx8qxp-pxl2dpi: Fix NULL pointer dereference in imx8qxp_pxl2dpi_bridge_destroy()
>>>       commit: db7e7ea838c916ee4cdf26bee126fd36f58295dc
>>
>> Any reason why patch 3/3 is not applied?
> 
> Yes, the reason is there's a patch conflict and I still have to find out
> how to handle it.
> 
> Patch 3 by the rules [0] should go to drm-misc-fixes because the bug (added
> by [1]) is already on Linus' master tree (since v6.17), but it does not
> apply there due to a conflict with an unrelated change [2] currently on
> drm-misc-next.
> 
> Note that [1] and [2] are the two commits mentioned in your 'Fixes: 'tags.
> 
> I had a chat with Maxime on #dir-devel about how to handle this situation
> but still haven't got a final answer.
> 
> I guess the correct way is:
> 
>  1. apply patch 3 on drm-misc-next, where it applies cleanly
>  2. send a modified patch for drm-misc-fixes, to fix ASAP the master branch

The conflict between the modified patch and commit [2] still needs to
be addressed in the future, right?  Not sure if there is any proper
process to address that.

I think it's acceptable to wait for a while and apply 3/3 after commit [2]
shows up in the master branch, because i.MX8QXP pixel combiner is not
added to device tree yet, that is, no one uses it for now.

> 
> Would you send the patch as in item 2, so it can be applied to
> drm-misc-fixes and have master fixed ASAP? Note iit should not mention [2]
> in the Fixes: tag because [2] is not yet on master. I can send it of course
> but you can test on hardware so that would be the best option (and I'm a
> bit overloaded at the moment).
> 
> [0] https://drm.pages.freedesktop.org/maintainer-tools/committer/committer-drm-misc.html
> [1] commit 99764593528f ("drm/bridge: imx8qxp-pixel-combiner: convert to devm_drm_bridge_alloc() API")
> [2] commit ae754f049ce1 ("drm/bridge: imx8qxp-pixel-combiner: get/put the next bridge")
> 
> Luca
> 
> --
> Luca Ceresoli, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com/

-- 
Regards,
Liu Ying
Re: (subset) [PATCH 0/3] drm/bridge: imx: A few fixes
Posted by Luca Ceresoli 1 week, 4 days ago
Hello Liu,

On Wed Jan 28, 2026 at 4:26 PM CET, Luca Ceresoli wrote:
>> Any reason why patch 3/3 is not applied?
>
> Yes, the reason is there's a patch conflict and I still have to find out
> how to handle it.
>
> Patch 3 by the rules [0] should go to drm-misc-fixes because the bug (added
> by [1]) is already on Linus' master tree (since v6.17), but it does not
> apply there due to a conflict with an unrelated change [2] currently on
> drm-misc-next.
>
> Note that [1] and [2] are the two commits mentioned in your 'Fixes: 'tags.
>
> I had a chat with Maxime on #dir-devel about how to handle this situation
> but still haven't got a final answer.
>
> I guess the correct way is:
>
>  1. apply patch 3 on drm-misc-next, where it applies cleanly
>  2. send a modified patch for drm-misc-fixes, to fix ASAP the master branch
>
> Would you send the patch as in item 2, so it can be applied to
> drm-misc-fixes and have master fixed ASAP? Note iit should not mention [2]
> in the Fixes: tag because [2] is not yet on master. I can send it of course
> but you can test on hardware so that would be the best option (and I'm a
> bit overloaded at the moment).

Nevermind, I've just sent it:
https://lore.kernel.org/lkml/20260128-drm-bridge-fix-imx8qxp-pixel-combiner-null-deref-v1-0-2138d0933cf1@bootlin.com/

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com