[PATCH 4/4] mm/kasan: make kasan=on|off take effect for all three modes

[Sabyrzhan Tasbolatov]

On Tue, Aug 5, 2025 at 11:34 AM Baoquan He <bhe at redhat.com> wrote:
>
> Now everything is ready, set kasan=off can disable kasan for all
> three modes.
>

Hello,

I've been working on this already and a different approach
with the Kconfig ARCH_DEFER_KASAN has been proposed.

Please see v4 thread.
https://lore.kernel.org/all/20250805142622.560992-1-snovitoll@gmail.com/

It also covers the printing in a single KASAN codebase, instead of
printing "KASAN intiilaized" in arch/* code.
Also covers the enabling KASAN via kasan_enable() for all 3 modes.

It's up to KASAN maintainers to choose either version.
I just need the confirmation now if I should proceed with v5,
or your version if it covers all arch and cases should be picked up.

Thanks

> Signed-off-by: Baoquan He <bhe at redhat.com>
> ---
>  include/linux/kasan-enabled.h | 11 +----------
>  1 file changed, 1 insertion(+), 10 deletions(-)
>
> diff --git a/include/linux/kasan-enabled.h b/include/linux/kasan-enabled.h
> index 32f2d19f599f..b5857e15ef14 100644
> --- a/include/linux/kasan-enabled.h
> +++ b/include/linux/kasan-enabled.h
> @@ -8,30 +8,21 @@ extern bool kasan_arg_disabled;
>
>  DECLARE_STATIC_KEY_FALSE(kasan_flag_enabled);
>
> -#ifdef CONFIG_KASAN_HW_TAGS
> -
>  static __always_inline bool kasan_enabled(void)
>  {
>         return static_branch_likely(&kasan_flag_enabled);
>  }
>
> +#ifdef CONFIG_KASAN_HW_TAGS
>  static inline bool kasan_hw_tags_enabled(void)
>  {
>         return kasan_enabled();
>  }
> -
>  #else /* CONFIG_KASAN_HW_TAGS */
> -
> -static inline bool kasan_enabled(void)
> -{
> -       return IS_ENABLED(CONFIG_KASAN);
> -}
> -
>  static inline bool kasan_hw_tags_enabled(void)
>  {
>         return false;
>  }
> -
>  #endif /* CONFIG_KASAN_HW_TAGS */
>
>  #endif /* LINUX_KASAN_ENABLED_H */
> --
> 2.41.0
>
>