Re: [PATCH v7 12/15] sh: Drop cache flush of the zero page at boot

[Mike Rapoport]

On Fri, May 29, 2026 at 05:02:03PM +0200, Ard Biesheuvel wrote:
> From: Ard Biesheuvel <ardb@xxxxxxxxxx>
> 
> SuperH performs cache maintenance on the zero page during boot,
> presumably because before commit
> 
>   6215d9f4470f ("arch, mm: consolidate empty_zero_page")
> 
> the zero page did double duty as a boot params region, and was cleared
> separately, as it was not part of BSS. The memset() in question was
> dropped by that commit, but the __flush_wback_region() call remained.
> 
> As empty_zero_page[] has been moved to BSS, it can be treated as any
> other BSS memory, and so the cache flush can be dropped.
> 
> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> Cc: Rich Felker <dalias@xxxxxxxx>
> Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
> Cc: Mike Rapoport <rppt@xxxxxxxxxx>
> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>

Acked-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>

> ---
>  arch/sh/mm/init.c | 3 ---
>  1 file changed, 3 deletions(-)

-- 
Sincerely yours,
Mike.