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Date:   Thu, 6 Oct 2022 10:18:24 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Jim Mattson <jmattson@google.com>
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        benh@kernel.crashing.org, stable@vger.kernel.org
Subject: Re: [PATCH] x86/speculation: Mitigate eIBRS PBRSB predictions with
 WRMSR
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On Wed, Oct 05, 2022 at 04:46:12PM -0700, Jim Mattson wrote:

>                 rmb();

Since we're not doing memory ordering but speculation hardening, this is
completely the wrong way to spell LFENCE. Please use barrier_nospec() in
those cases.

And as has already been pointed out, there's one of those just two lines
down already.

Also, what Andrew said.