Re: [PATCH] efi: Return EFI_RESERVED_TYPE in efi_mem_type() for absent addresses

From: Ard Biesheuvel
Date: Wed Nov 06 2019 - 12:02:11 EST


On Tue, 5 Nov 2019 at 21:39, Anshuman Khandual
<anshuman.khandual@xxxxxxx> wrote:
>
> The function efi_mem_type() is expected (per documentation above) to return
> EFI_RESERVED_TYPE when a given physical address is not present in the EFI
> memory map. Even though EFI_RESERVED_TYPE is not getting checked explicitly
> anywhere in the callers, it is always better to return expected values.
>
> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> Cc: linux-efi@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

This reverts commit f99afd08a45fbbd9ce35a7624ffd1d850a1906c0.

Could you explain why it is better to fix the code than fix the comment?

> ---
> drivers/firmware/efi/efi.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 69f00f7453a3..bdda90a4601e 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -914,7 +914,7 @@ int efi_mem_type(unsigned long phys_addr)
> (md->num_pages << EFI_PAGE_SHIFT))))
> return md->type;
> }
> - return -EINVAL;
> + return EFI_RESERVED_TYPE;
> }
> #endif
>
> --
> 2.20.1
>