Re: [PATCH] x86/speculation: Mitigate eIBRS PBRSB predictions with WRMSR

From: Peter Zijlstra
Date: Thu Oct 06 2022 - 04:19:05 EST

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.