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Date: Fri, 4 May 2018 18:09:04 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 3/5] SSB extra 1
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To: speck@linutronix.de
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On Fri, 4 May 2018, speck for Andi Kleen wrote:

> > > Ahhh, that's an interesting point.  Are you thinking that we add a BPF
> > > "instruction" to enable or disable the mitigations, and then have the
> > > verifier insert it as the first instruction and then before any exit
> > > instructions?  Is there some precedent for doing this?
> > 
> > Dunno, but it would be the obvious thing to do I think.
> 
> Other option would be a preempt notifier migrating the SSB state?

Why so? Because it's more complex than just using the TIF_RDS flag which
gets evaluated anyway?

Thanks,

	tglx