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Date: Fri, 19 Apr 2024 17:00:33 +0200
From: Borislav Petkov <bp@alien8.de>
To: Sean Christopherson <seanjc@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Peter Zijlstra <peterz@infradead.org>, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Geert Uytterhoeven <geert@linux-m68k.org>
Subject: Re: [PATCH 2/2] cpu: Ignore "mitigations" kernel parameter if
 CPU_MITIGATIONS=n
Message-ID: <20240419150033.GBZiKHEUVzwz1LUDS5@fat_crate.local>
References: <20240417001507.2264512-1-seanjc@google.com>
 <20240417001507.2264512-3-seanjc@google.com>
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In-Reply-To: <20240417001507.2264512-3-seanjc@google.com>

On Tue, Apr 16, 2024 at 05:15:07PM -0700, Sean Christopherson wrote:
> Explicitly disallow enabling mitigations at runtime for kernels that were
> built with CONFIG_CPU_MITIGATIONS=n, which currently is possible only on
> x86 (via x86's SPECULATION_MITIGATIONS menuconfig).

Hm, so the umbrella term is CPU_MITIGATIONS, the x86-one is
SPECULATION_MITIGATIONS.

I wanna streamline our namespacing and say, the arch agnostic term
should be CPU_MITIGATIONS and the x86 one should be then
X86_CPU_MITIGATIONS, the Arm one would be ARM_CPU_MITIGATIONS and so on.

This way we can stick all kinds of special mitigations code - not only
speculative execution ones - under those config items and have it all
straight from the get-go.

And I think we should do it now, before it all propagates down the tree
and becomes a lot harder to rename.

Thoughts?

Thx.

-- 
Regards/Gruss,
    Boris.

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