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Date:   Sat, 12 Aug 2023 13:32:56 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Josh Poimboeuf <jpoimboe@kernel.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, David.Kaplan@amd.com,
        Andrew.Cooper3@citrix.com, gregkh@linuxfoundation.org
Subject: Re: [RFC][PATCH 06/17] x86/cpu: Add SRSO untrain to retbleed=
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On Fri, Aug 11, 2023 at 12:27:48PM +0200, Borislav Petkov wrote:
> On Thu, Aug 10, 2023 at 12:10:03PM -0400, Josh Poimboeuf wrote:
> > I tend to agree that SRSO is a new issue and should have its own sysfs
> > and cmdline options (though a separate CONFIG option is overkill IMO).
> 
> Yeah, there's a patch floating around adding a config option for every
> mitigation. Apparently people want to build-time disable them all.

So I really hate that .Kconfig explosion, that's the very last thing we
need :-( More random options that can cause build time trouble.

I might see value in one knob that kills all speculation nonsense at
build time, but not one per mitigation, that's maddness.