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Date:   Thu, 22 Oct 2020 21:28:29 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        Sultan Alsawaf <sultan@kerneltoast.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        kitsunyan <kitsunyan@airmail.cc>,
        "Brown, Len" <len.brown@intel.com>, X86 ML <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] x86/msr: do not warn on writes to OC_MAILBOX
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On Wed, Oct 21, 2020 at 06:11:09AM -0700, Srinivas Pandruvada wrote:
> That is the problem. There is no public document.

Well, considering how important this functionality has become, maybe
they should be made public and maybe there should be a kernel undervolt
driver, as peterz suggests.

> > I dunno.  Maybe we should try it for *one* model and see how it goes.
> > Maybe start with the one we're already poking from inside the kernel.

Yes, we can surely give it a try.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette