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Message-ID: <1516290915.4937.156.camel@infradead.org>
Subject: Re: [PATCH] x86/mce: Make machine check speculation protected
From:   David Woodhouse <dwmw2@infradead.org>
To:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>
Cc:     x86@kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Borislav Petkov <bp@alien8.de>
In-Reply-To: <alpine.DEB.2.20.1801181626290.1847@nanos>
References: <alpine.DEB.2.20.1801181626290.1847@nanos>
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Date:   Thu, 18 Jan 2018 16:55:15 +0100
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On Thu, 2018-01-18 at 16:28 +0100, Thomas Gleixner wrote:
> The machine check idtentry uses an indirect branch directly from the low
> level code. This evades the speculation protection.
>=20
> Replace it by a direct call into C code and issue the indirect call there
> so the compiler can apply the proper speculation protection.
>=20
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>

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