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Date:   Mon, 17 Jun 2019 22:21:51 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Tim Chen <tim.c.chen@linux.intel.com>
cc:     Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>,
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        Jiri Kosina <jikos@kernel.org>,
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        Mark Gross <mgross@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>, x86@kernel.org
Subject: Re: [PATCH v3] Documentation: Add section about CPU vulnerabilities
 for Spectre
In-Reply-To: <c63945d34bfc9df2412f813d0b9b3a321a65de5d.1560795378.git.tim.c.chen@linux.intel.com>
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References: <c63945d34bfc9df2412f813d0b9b3a321a65de5d.1560795378.git.tim.c.chen@linux.intel.com>
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Tim,

On Mon, 17 Jun 2019, Tim Chen wrote:

> +Spectre variant 1 attacks take advantage of speculative execution of
> +conditional branches, while Spectre variant 2 attacks use speculative
> +execution of indirect branches to leak privileged memory. See [1] [5]
> +[7] [10] [11].

It would be great to actually link these [N] to the actual http link at the
bottom. No idea what's the best way to do that.

Jonathan?

> +Mitigation control on the kernel command line
> +---------------------------------------------
> +
> +Spectre variant 2 mitigation can be disabled or force enabled at the
> +kernel command line.

The below renders horribly when converted to HTML

You probably want to wrap these into a table

> +	nospectre_v2	[X86] Disable all mitigations for the Spectre variant 2
> +			(indirect branch prediction) vulnerability. System may
> +			allow data leaks with this option, which is equivalent
> +			to spectre_v2=off.
> +
> +
> +        spectre_v2=     [X86] Control mitigation of Spectre variant 2
> +			(indirect branch speculation) vulnerability.
> +			The default operation protects the kernel from
> +			user space attacks.

Maybe Jonathan has a better idea.

Other than those formatting detail, this looks really good. Well done!

Thanks,

	tglx