[PATCH v4 14/29] arm64: mask out POIndex when modifying a PTE

[Anshuman Khandual]

On 5/3/24 18:31, Joey Gouly wrote:
> When a PTE is modified, the POIndex must be masked off so that it can be modified.
> 
> Signed-off-by: Joey Gouly <joey.gouly at arm.com>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Will Deacon <will at kernel.org>
> Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>

Reviewed-by: Anshuman Khandual <anshuman.khandual at arm.com>

> ---
>  arch/arm64/include/asm/pgtable.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index afdd56d26ad7..5c970a9cca67 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -1028,7 +1028,8 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
>  	 */
>  	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
>  			      PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP |
> -			      PTE_ATTRINDX_MASK;
> +			      PTE_ATTRINDX_MASK | PTE_PO_IDX_MASK;
> +
>  	/* preserve the hardware dirty information */
>  	if (pte_hw_dirty(pte))
>  		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));