Re: [PATCH v7 7/9] mm: Add address parameter to arch_validate_prot()

From: Michael Ellerman
Date: Thu Aug 10 2017 - 09:20:33 EST


Khalid Aziz <khalid.aziz@xxxxxxxxxx> writes:

> A protection flag may not be valid across entire address space and
> hence arch_validate_prot() might need the address a protection bit is
> being set on to ensure it is a valid protection flag. For example, sparc
> processors support memory corruption detection (as part of ADI feature)
> flag on memory addresses mapped on to physical RAM but not on PFN mapped
> pages or addresses mapped on to devices. This patch adds address to the
> parameters being passed to arch_validate_prot() so protection bits can
> be validated in the relevant context.
>
> Signed-off-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx>
> Cc: Khalid Aziz <khalid@xxxxxxxxxxxxxx>
> ---
> v7:
> - new patch
>
> arch/powerpc/include/asm/mman.h | 2 +-
> arch/powerpc/kernel/syscalls.c | 2 +-
> include/linux/mman.h | 2 +-
> mm/mprotect.c | 2 +-
> 4 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
> index 30922f699341..bc74074304a2 100644
> --- a/arch/powerpc/include/asm/mman.h
> +++ b/arch/powerpc/include/asm/mman.h
> @@ -40,7 +40,7 @@ static inline bool arch_validate_prot(unsigned long prot)
> return false;
> return true;
> }
> -#define arch_validate_prot(prot) arch_validate_prot(prot)
> +#define arch_validate_prot(prot, addr) arch_validate_prot(prot)

This can be simpler, as just:

#define arch_validate_prot arch_validate_prot

cheers