From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arjan van de Ven <arjan@linux.intel.com>
Subject: Re: [RFC,05/10] x86/speculation: Add basic IBRS support
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Date: Wed, 31 Jan 2018 07:11:54 -0800
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Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        David Woodhouse <dwmw2@infradead.org>,
        Eduardo Habkost <ehabkost@redhat.com>,
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        Andi Kleen <ak@linux.intel.com>,
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        Asit Mallick <asit.k.mallick@intel.com>,
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        Dan Williams <dan.j.williams@intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
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        "H . Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>,
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To: Thomas Gleixner <tglx@linutronix.de>,
        Christophe de Dinechin <christophe.de.dinechin@gmail.com>
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On 1/31/2018 2:15 AM, Thomas Gleixner wrote:

> Good luck with making all that work.

on the Intel side we're checking what we can do that works and doesn't break
things right now; hopefully we just end up with a bit in the arch capabilities
MSR for "you should do RSB stuffing" and then the HV's can emulate that.

(people sometimes think that should be a 5 minute thing, but we need to check
many cpu models/etc to make sure a bit we pick is really free etc which makes
it take longer than some folks have patience for)