linux-kernel - Re: [PATCH 3/6] x86-mce: Clear CMCI enable on all claimed CMCI banks before reboot.

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Message-ID: <20140710183001.GD5603@pd.tnic>
Date:	Thu, 10 Jul 2014 20:30:01 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Havard Skinnemoen <hskinnemoen@...gle.com>
Cc:	"Luck, Tony" <tony.luck@...el.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Ewout van Bekkum <ewout@...gle.com>
Subject: Re: [PATCH 3/6] x86-mce: Clear CMCI enable on all claimed CMCI banks
 before reboot.

On Thu, Jul 10, 2014 at 10:56:05AM -0700, Havard Skinnemoen wrote:
> Even on kexec-enabled kernels, we might be doing a regular BIOS boot.
> Is there any way to detect that we're doing a kexec boot and only
> clearing the MSRs in that case?

What Tony said: if the processor resets, those MSRs are cleared, forget
BIOS.

I dunno though whether the processor gets reset during kexec though. It
needs code staring...

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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