lib/crc: arm64: Drop check for CONFIG_KERNEL_MODE_NEON

[PATCH] lib/crc: arm64: Drop check for CONFIG_KERNEL_MODE_NEON

Posted by Eric Biggers 3 weeks, 2 days ago

CONFIG_KERNEL_MODE_NEON is always enabled on arm64, and it always has
been since its introduction in 2013.  Given that and the fact that the
usefulness of kernel-mode NEON has only been increasing over time,
checking for this option in arm64-specific code is unnecessary.  Remove
this check from lib/crc/ to simplify the code and prevent any future
bugs where e.g. code gets disabled due to a typo in this logic.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---

This patch is targeting crc-next
(https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=crc-next)

 lib/crc/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/crc/Kconfig b/lib/crc/Kconfig
index cca228879bb5a..52e216f397468 100644
--- a/lib/crc/Kconfig
+++ b/lib/crc/Kconfig
@@ -46,11 +46,11 @@ config CRC_T10DIF
 
 config CRC_T10DIF_ARCH
 	bool
 	depends on CRC_T10DIF && CRC_OPTIMIZATIONS
 	default y if ARM && KERNEL_MODE_NEON
-	default y if ARM64 && KERNEL_MODE_NEON
+	default y if ARM64
 	default y if PPC64 && ALTIVEC
 	default y if RISCV && RISCV_ISA_ZBC
 	default y if X86
 
 config CRC32

base-commit: c13cee2fc7f137dd25ed50c63eddcc578624f204
-- 
2.53.0

Re: [PATCH] lib/crc: arm64: Drop check for CONFIG_KERNEL_MODE_NEON

Posted by Eric Biggers 2 weeks, 6 days ago

On Sat, Mar 14, 2026 at 10:57:44AM -0700, Eric Biggers wrote:
> CONFIG_KERNEL_MODE_NEON is always enabled on arm64, and it always has
> been since its introduction in 2013.  Given that and the fact that the
> usefulness of kernel-mode NEON has only been increasing over time,
> checking for this option in arm64-specific code is unnecessary.  Remove
> this check from lib/crc/ to simplify the code and prevent any future
> bugs where e.g. code gets disabled due to a typo in this logic.
> 
> Signed-off-by: Eric Biggers <ebiggers@kernel.org>
> ---
> 
> This patch is targeting crc-next
> (https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=crc-next)

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=crc-next

- Eric

Re: [PATCH] lib/crc: arm64: Drop check for CONFIG_KERNEL_MODE_NEON

Posted by Ard Biesheuvel 2 weeks, 6 days ago


On Sat, 14 Mar 2026, at 18:57, Eric Biggers wrote:
> CONFIG_KERNEL_MODE_NEON is always enabled on arm64, and it always has
> been since its introduction in 2013.  Given that and the fact that the
> usefulness of kernel-mode NEON has only been increasing over time,
> checking for this option in arm64-specific code is unnecessary.  Remove
> this check from lib/crc/ to simplify the code and prevent any future
> bugs where e.g. code gets disabled due to a typo in this logic.
>
> Signed-off-by: Eric Biggers <ebiggers@kernel.org>
> ---
>
> This patch is targeting crc-next
> (https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=crc-next)
>
>  lib/crc/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>

Acked-by: Ard Biesheuvel <ardb@kernel.org>

> diff --git a/lib/crc/Kconfig b/lib/crc/Kconfig
> index cca228879bb5a..52e216f397468 100644
> --- a/lib/crc/Kconfig
> +++ b/lib/crc/Kconfig
> @@ -46,11 +46,11 @@ config CRC_T10DIF
> 
>  config CRC_T10DIF_ARCH
>  	bool
>  	depends on CRC_T10DIF && CRC_OPTIMIZATIONS
>  	default y if ARM && KERNEL_MODE_NEON
> -	default y if ARM64 && KERNEL_MODE_NEON
> +	default y if ARM64
>  	default y if PPC64 && ALTIVEC
>  	default y if RISCV && RISCV_ISA_ZBC
>  	default y if X86
> 
>  config CRC32
>
> base-commit: c13cee2fc7f137dd25ed50c63eddcc578624f204
> -- 
> 2.53.0