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Re: [PATCH v2 3/6] x86/cpu: Re-apply forced caps every time cpu caps are re-read

From Borislav Petkov <bp@alien8.de>
Newsgroups linux.kernel
Subject Re: [PATCH v2 3/6] x86/cpu: Re-apply forced caps every time cpu caps are re-read
Date 2017-01-19 12:50 +0100
Message-ID <t1jo6-10B-7@gated-at.bofh.it> (permalink)
References <t13W1-83l-5@gated-at.bofh.it> <t13W3-83l-45@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On Wed, Jan 18, 2017 at 11:15:39AM -0800, Andy Lutomirski wrote:
> Calling get_cpu_cap() will reset a bunch of CPU features.  This will
> cause the system to lose track of force-set and force-cleared
> featueres in the words that are reset until the end of CPU

features

> initialization.  This can cause X86_FEATURE_FPU, for example, to
> change back and forth during boot and potentially confuse CPU setup.
> 
> To minimize the chance of confusion, re-apply forced caps every time
> get_cpu_cap() is called.
> 
> Signed-off-by: Andy Lutomirski <luto@kernel.org>

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

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Thread

[PATCH v2 3/6] x86/cpu: Re-apply forced caps every time cpu caps are re-read Andy Lutomirski <luto@kernel.org> - 2017-01-18 20:20 +0100
  Re: [PATCH v2 3/6] x86/cpu: Re-apply forced caps every time cpu caps  are re-read Borislav Petkov <bp@alien8.de> - 2017-01-19 12:50 +0100
  [tip:x86/fpu] x86/cpu: Re-apply forced caps every time CPU caps are  re-read tip-bot for Andy Lutomirski <tipbot@zytor.com> - 2017-01-25 12:50 +0100

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