[PATCH v4 17/29] arm64: implement PKEYS support

[Catalin Marinas]

On Fri, May 03, 2024 at 02:01:35PM +0100, Joey Gouly wrote:
> @@ -163,7 +182,8 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
>  #define pte_access_permitted_no_overlay(pte, write) \
>  	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
>  #define pte_access_permitted(pte, write) \
> -	pte_access_permitted_no_overlay(pte, write)
> +	(pte_access_permitted_no_overlay(pte, write) && \
> +	por_el0_allows_pkey(FIELD_GET(PTE_PO_IDX_MASK, pte_val(pte)), write, false))

I'm still not entirely convinced on checking the keys during fast GUP
but that's what x86 and powerpc do already, so I guess we'll follow the
same ABI.

Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>