[PATCH 4/7] x86: mtrr: Abort if requested size is not power of 2

[Simon Glass]

On Sat, 31 Jul 2021 at 02:45, Bin Meng <bmeng.cn at gmail.com> wrote:
>
> The size parameter of mtrr_add_request() and mtrr_set_next_var()
> shall be power of 2, otherwise the logic creates a mask that does
> not meet the requirement of IA32_MTRR_PHYSMASK register.
>
> Programming such a mask value to IA32_MTRR_PHYSMASK generates #GP.
>
> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
> ---
>
>  arch/x86/cpu/mtrr.c         | 7 +++++++
>  arch/x86/include/asm/mtrr.h | 7 ++++---
>  2 files changed, 11 insertions(+), 3 deletions(-)

Reviewed-by: Simon Glass <sjg at chromium.org>
Tested on chromebook_coral, chromebook_samus, chromebook_link, minnowmax
Tested-by: Simon Glass <sjg at chromium.org>