linux-kernel - Re: [PATCH 22/25] x86/mcheck: Do the init in one place

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Message-ID: <20161107201224.7xazmhgm7bogkrw5@pd.tnic>
Date:   Mon, 7 Nov 2016 21:12:24 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     "Luck, Tony" <tony.luck@...el.com>
Cc:     Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        linux-kernel@...r.kernel.org, rt@...utronix.de,
        linux-edac@...r.kernel.org, x86@...nel.org,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH 22/25] x86/mcheck: Do the init in one place

On Mon, Nov 07, 2016 at 10:55:24AM -0800, Luck, Tony wrote:
> I don't think that helps as much as you'd like it to help (at
> least on Intel). A broadcast machine check that finds the boot
> CPU has set CR4[MCE]=1 is still going to end up in reset if any
> other CPU still has CR4[MCE]=0

By leaving/moving the setting of CR4 earlier on all cores, we'll
at least make the possible window for such potential resets a lot
smaller...

-- 
Regards/Gruss,
    Boris.

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