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Date:   Fri, 11 Aug 2023 12:27:48 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Josh Poimboeuf <jpoimboe@kernel.org>
Cc:     Peter Zijlstra <peterz@infradead.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 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.

> The mitigations are unfortunately intertwined, but we've been in that
> situation several times before (e.g., spectre_v2 + intel retbleed).

Yap.

And if you recall, keeping Intel Retbleed from AMD Retbleed apart was
already a PITA at the time so adding yet another one behind that flag
would be madness.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette