Re: [PATCH v4 06/12] x86/mtrr: replace vendor tests in MTRR code

From: Borislav Petkov
Date: Mon Mar 27 2023 - 03:15:05 EST


On Mon, Mar 27, 2023 at 07:43:58AM +0200, Juergen Gross wrote:
> The is_cpu() checks are either in functions reachable only with mtrr_if being
> set, or are testing for INTEL, which is replaced by the test of mtrr_if being
> &generic_mtrr_ops as written in the commit message.

I went through all call sites... it seems like what you're saying should
work. I guess this mtrr_if check was added as a precaution in 2002 as
part of a cleanup:

commit 8fbdcb188e31ac901e216b466b97e90e8b057daa
Author: Dave Jones <davej@xxxxxxx>
Date: Wed Aug 14 21:14:22 2002 -0700

[PATCH] Modular x86 MTRR driver.

This patch from Pat Mochel cleans up the hell that was mtrr.c
into something a lot more modular and easy to understand, by
doing the implementation-per-file as has been done to various
other things by Pat and myself over the last months.

It's functionally identical from a kernel internal point of view,
and a userspace point of view, and is basically just a very large
code clean up.

So let's see what catches fire...

Thx.

--
Regards/Gruss,
Boris.

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