linux-kernel - Re: [tip: x86/core] x86/alternative: Patch a single alternative location only once

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Message-ID: <20251014141245.GCaO5aXSQqglFrT9Iy@fat_crate.local>
Date: Tue, 14 Oct 2025 16:12:45 +0200
From: Borislav Petkov <bp@...en8.de>
To: Jürgen Groß <jgross@...e.com>
Cc: linux-kernel@...r.kernel.org, linux-tip-commits@...r.kernel.org,
	"Peter Zijlstra (Intel)" <peterz@...radead.org>, x86@...nel.org
Subject: Re: [tip: x86/core] x86/alternative: Patch a single alternative
 location only once

On Tue, Oct 14, 2025 at 04:08:47PM +0200, Jürgen Groß wrote:
> And just for the record: NMI handling is using ALTERNATIVE_2, so you
> can't just "disable interrupts" and be sure it will work.

Are you fixing anything you're actually hitting while patching alternatives or
are you talking hypothetically here?

Because I can't think of an easy way to trigger NMIs that early during boot,
when not even SMP is up.

-- 
Regards/Gruss,
    Boris.

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