Re: [PATCH v2] riscv: mm: fix NOCACHE_THEAD does not set bit[61] correctly

From: Alexandre Ghiti
Date: Wed Feb 21 2024 - 09:02:02 EST


Hi Yangyu,

On Wed, Feb 21, 2024 at 4:04 AM Yangyu Chen <cyy@xxxxxxxxxxxx> wrote:
>
> Previous commit dbfbda3bd6bf ("riscv: mm: update T-Head memory type
> definitions") from patch [1] missed a `<` for bit shifting, result in
> bit(61) does not set in _PAGE_NOCACHE_THEAD and leaves bit(0) set instead.
> This patch get this fixed.
>
> Changes since v1:
> * reword commit message and add reviewed-by
>
> Link: https://lore.kernel.org/linux-riscv/20230912072510.2510-1-jszhang@xxxxxxxxxx/ [1]
> Fixes: dbfbda3bd6bf ("riscv: mm: update T-Head memory type definitions")
> Signed-off-by: Yangyu Chen <cyy@xxxxxxxxxxxx>
> Reviewed-by: Guo Ren <guoren@xxxxxxxxxx>
> Reviewed-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
> ---
> arch/riscv/include/asm/pgtable-64.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
> index b42017d76924..b99bd66107a6 100644
> --- a/arch/riscv/include/asm/pgtable-64.h
> +++ b/arch/riscv/include/asm/pgtable-64.h
> @@ -136,7 +136,7 @@ enum napot_cont_order {
> * 10010 - IO Strongly-ordered, Non-cacheable, Non-bufferable, Shareable, Non-trustable
> */
> #define _PAGE_PMA_THEAD ((1UL << 62) | (1UL << 61) | (1UL << 60))
> -#define _PAGE_NOCACHE_THEAD ((1UL < 61) | (1UL << 60))
> +#define _PAGE_NOCACHE_THEAD ((1UL << 61) | (1UL << 60))
> #define _PAGE_IO_THEAD ((1UL << 63) | (1UL << 60))
> #define _PAGE_MTMASK_THEAD (_PAGE_PMA_THEAD | _PAGE_IO_THEAD | (1UL << 59))
>
> --
> 2.43.0
>

I feel pretty confident on this one :)

Reviewed-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>

Thanks,

Alex