Re: [PATCH v3 05/27] arm64: Extract sysreg definitions

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Dropping `kernel-hwcap.h` from Kbuild's `targets` array causes it to be unconditionally rebuilt on every make invocation, breaking incremental builds.
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commit 56233effa49d4a8119244cffc6426b8b9f08a322
Author: Nina Schoetterl-Glausch <nsg@linux.ibm.com>

arm64: Extract sysreg definitions

This commit splits all definitions that can be used by non-native
architectures into a separate file sysreg-defs.h. The generated sysreg
definitions are placed into sysreg-defs-gen.h, and the tools Makefiles
are updated to accommodate this change.

> diff --git a/arch/arm64/tools/Makefile b/arch/arm64/tools/Makefile
> index a94b3d9caad64..4147187b66273 100644
> --- a/arch/arm64/tools/Makefile
> +++ b/arch/arm64/tools/Makefile
[ ... ]
> -kapisyshdr-y := cpucap-defs.h kernel-hwcap.h sysreg-defs.h
> +include $(srctree)/arch/arm64/tools/Makefile.sysreg
>  
> +kapisyshdr-y := cpucap-defs.h kernel-hwcap.h
>  kapi-hdrs-y := $(addprefix $(kapi)/, $(kapisyshdr-y))
>  
> -targets += $(addprefix ../../../, $(kapi-hdrs-y))
> +targets += $(addprefix ../../../, $(kapi)/cpucap-defs.h)

[Severity: Medium]
Does removing kernel-hwcap.h from the targets array break incremental builds?

Kbuild's if_changed macro requires all generated targets to be listed in the
targets variable so that their corresponding .cmd files are included to track
command lines and prerequisites.

Without this, won't Kbuild assume the target must be rebuilt every time,
updating the timestamp of kernel-hwcap.h on every build and triggering
unnecessary recompilation of all files that depend on it?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260529155050.2902245-1-seiden@linux.ibm.com?part=5