Re: [PATCH v5 08/17] dt-bindings: riscv: Require block-size for Zicbom, Zicbop, and Zicboz

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] JSON schema 'if' blocks incorrectly match nodes missing the 'riscv,isa-extensions' property, erroneously enforcing block-size requirements on legacy device trees.
--

commit 08f47eb689e1ffc05b399844b4f633278d53641f
Author: Guodong Xu <docular.xu@gmail.com>

dt-bindings: riscv: Require block-size for Zicbom, Zicbop, and Zicboz

This commit updates the RISC-V extensions schema to make block-size properties 
mandatory for the Zicbom, Zicbop, and Zicboz extensions. The goal is to catch 
missing properties during dtbs_check since these extensions do not have a 
default cache block size.

> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> index 5ffc40d599c02..f4dd34d446c02 100644
> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml

[ ... ]

> @@ -1142,6 +1142,32 @@ allOf:
>            not:
>              contains:
>                const: zilsd
> +  # All three Zicbo* extensions require their block size property as there's no
> +  # default.
> +  - if:
> +      properties:
> +        riscv,isa-extensions:
> +          contains:
> +            const: zicbom
> +    then:
> +      required:
> +        - riscv,cbom-block-size

[Severity: Medium]
Does this JSON schema 'if' block inadvertently evaluate to true for nodes
missing the 'riscv,isa-extensions' property entirely?

In JSON schema validation, the 'properties' keyword only applies constraints
to properties that are actually present in the instance. If a device tree
node lacks 'riscv,isa-extensions' (such as legacy nodes using only the
deprecated 'riscv,isa' property), this 'if' condition will vacuously succeed.

Will this erroneously enforce the 'riscv,cbom-block-size' requirement on
all those legacy nodes during dtbs_check? 

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260701-rva23u64-hwprobe-v2-v5-0-2c61f94a695a@gmail.com?part=8