Re: [PATCH] arm64/mm: Replace open encodings with PXD_TABLE_BIT

[Ryan Roberts <ryan.roberts@arm.com>]

On 02/12/2024 08:38, Anshuman Khandual wrote:
> [pgd|p4d]_bad() helpers have open encodings for their respective table bits
> which can be replaced with corresponding macros. This makes things clearer,
> thus improving their readability as well.
> 
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Ryan Roberts <ryan.roberts@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>

Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>

> ---
> This patch applies on v6.13-rc1
> 
>  arch/arm64/include/asm/pgtable.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 6986345b537a..e20b80229910 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -896,7 +896,7 @@ static inline bool mm_pud_folded(const struct mm_struct *mm)
>  	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
>  
>  #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
> -#define p4d_bad(p4d)		(pgtable_l4_enabled() && !(p4d_val(p4d) & 2))
> +#define p4d_bad(p4d)		(pgtable_l4_enabled() && !(p4d_val(p4d) & P4D_TABLE_BIT))
>  #define p4d_present(p4d)	(!p4d_none(p4d))
>  
>  static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
> @@ -1023,7 +1023,7 @@ static inline bool mm_p4d_folded(const struct mm_struct *mm)
>  	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
>  
>  #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
> -#define pgd_bad(pgd)		(pgtable_l5_enabled() && !(pgd_val(pgd) & 2))
> +#define pgd_bad(pgd)		(pgtable_l5_enabled() && !(pgd_val(pgd) & PGD_TABLE_BIT))
>  #define pgd_present(pgd)	(!pgd_none(pgd))
>  
>  static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)