Re: [PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The schema fails to require `#address-cells`, `#size-cells`, and `dma-ranges` on the parent node when the `non-pixel` and `pixel` subnodes are used.
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--- Patch [2]: [PATCH v2 02/12] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes ---
commit ba9132c7e393d239aeadc5fc3b8d92905c2ec775
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

This commit updates the sm8550-iris device tree binding to support per-stream
context bank subnodes by referencing qcom,venus-common.yaml. It drops the flat
"iommus" property from the required list and updates the example to use the new
"non-pixel" and "pixel" subnodes along with their supporting bus properties.

> diff --git a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> index 0400ca1bff05d..3d8ff5677bd4f 100644
> --- a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> @@ -98,10 +98,10 @@ required:
>    - interconnect-names
>    - resets
>    - reset-names
> -  - iommus
>    - dma-coherent
>  
>  allOf:
> +  - $ref: qcom,venus-common.yaml#

[Severity: Medium]
When referencing qcom,venus-common.yaml to support the new non-pixel and
pixel subnodes, is it possible for incomplete device trees to silently pass
validation?

In Documentation/devicetree/bindings/media/qcom,venus-common.yaml, the oneOf
check requires the non-pixel and pixel subnodes:

  - required:
      - non-pixel
      - pixel

However, it doesn't appear to enforce the presence of #address-cells,
#size-cells, and dma-ranges on the parent node when those subnodes are used.

If a device tree writer implements the new subnode configuration but forgets
to include these supporting bus properties in the parent node, could this
defective configuration pass dt_binding_check and dtbs_check, ultimately
leading to the DMA translation failures and SMMU page faults described in
the commit message?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260731-vpu_iommu_iova_handling-v2-0-da52b5228dbd@oss.qualcomm.com?part=2