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Subject: Re: [RFC,05/10] x86/speculation: Add basic IBRS support
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To:     Thomas Gleixner <tglx@linutronix.de>,
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From:   Arjan van de Ven <arjan@linux.intel.com>
Message-ID: <c40b9c17-bbb9-ad2b-7855-9fc7d857ad83@linux.intel.com>
Date:   Wed, 31 Jan 2018 07:11:54 -0800
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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)