Re: [PATCH 4/6] arch/riscv: Add bitrev.h file to support rev8 and brev8

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Selecting GENERIC_BITREVERSE without satisfying its dependency causes a Kconfig unmet dependency warning.
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commit b26322371528c694cf7ce4bf22b509fc4ef43133
Author: Jinjie Ruan <ruanjinjie@huawei.com>

arch/riscv: Add bitrev.h file to support rev8 and brev8

This commit adds <asm/bitrev.h> to efficiently implement bit reversal
using the 'rev8' and 'brev8' instructions from the RISC-V Zbkb extension.
It updates Kconfig to select GENERIC_BITREVERSE and HAVE_ARCH_BITREVERSE
to utilize these hardware instructions.

Link: https://docs.riscv.org/reference/isa/unpriv/b-st-ext.html

> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index d235396c45141..d32309846fa31 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -104,6 +104,7 @@ config RISCV
>  	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
>  	select GENERIC_ARCH_TOPOLOGY
>  	select GENERIC_ATOMIC64 if !64BIT
> +	select GENERIC_BITREVERSE

Will this select introduce a Kconfig unmet dependency regression?

In lib/Kconfig, GENERIC_BITREVERSE explicitly depends on BITREVERSE.

Selecting a symbol directly without also satisfying its dependencies forces
the target symbol on, which causes Kconfig warnings at build time when
BITREVERSE is disabled (for example, during allnoconfig builds).

Could this select also include BITREVERSE to satisfy the dependency chain?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260430211351.658193-1-ynorov@nvidia.com?part=4