Re: [PATCH v2 4/6] x86/mtrr: Fix PAT init handling when MTRR MSR is disabled

From	Borislav Petkov <bp@suse.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 4/6] x86/mtrr: Fix PAT init handling when MTRR MSR is disabled
Date	2016-03-22 18:10 +0100
Message-ID	<rfxYC-7FK-7@gated-at.bofh.it> (permalink)
References	<rdtw6-7MK-1@gated-at.bofh.it> <rdtw6-7MK-5@gated-at.bofh.it>
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Subject: [PATCH v2 4/6] x86/mtrr: Fix PAT init handling when MTRR MSR is disabled

s/ MSR//

On Wed, Mar 16, 2016 at 06:46:57PM -0600, Toshi Kani wrote:
> get_mtrr_state() calls pat_init() on BSP even if MTRR is disabled
> by its MSR.

s/by its MSR//

> This causes pat_init() to be called on BSP only since APs do not call

This doesn't cause that - get_mtrr_state() is called only on the BSP by
mtrr_bp_init().

> pat_init() when MTRR is disabled. This inconsistency between BSP and
> APs leads undefined behavior.

      leads to


> Move BSP's PAT init code from get_mtrr_state() to mtrr_bp_pat_init().
> Change mtrr_bp_init() to call mtrr_bp_pat_init() if MTRR is enabled.

No need for those.

> This keeps BSP's calling condition to pat_init() consistent with AP's,
> mtrr_ap_init() and mtrr_aps_init().

This one is fine.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
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Re: [PATCH v2 4/6] x86/mtrr: Fix PAT init handling when MTRR MSR is  disabled Borislav Petkov <bp@suse.de> - 2016-03-22 18:10 +0100
  Re: [PATCH v2 4/6] x86/mtrr: Fix PAT init handling when MTRR MSR is  disabled Toshi Kani <toshi.kani@hpe.com> - 2016-03-22 22:20 +0100

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