Re: [PATCH 01/17] x86: spec_ctrl: fix SPEC_CTRL initialization after kexec

From: Sean Christopherson
Date: Mon Sep 23 2019 - 18:27:39 EST


On Mon, Sep 23, 2019 at 01:34:21PM -0400, Andrea Arcangeli wrote:
> Per subject of the patch, 14 is also an optimization that while not a
> strict requirement, is somewhat related to the monolithic conversion
> because in fact it may naturally disappear if I rename the vmx/svm
> functions directly.
>
> 15 16 17 don't have the monolithic tag in the subject of the patch and
> they're obviously unrelated to the monolithic conversion, but when I
> did the first research on this idea of dropping kvm.ko a couple of
> months ago, things didn't really work well until I got rid of those
> few last retpolines too. If felt as if the large retpoline regression
> wasn't linear with the number of retpolines executed for each vmexit,
> and that it was more linear with the percentage of vmexits that hit on
> any number of retpolines. So while they're not part of the monolithic
> conversion I assumed they're required to run any meaningful benchmark.
>
> I can drop 15 16 17 from further submits of course, after clarifying
> benchmark should be only run on the v1 full set I posted earlier, or
> they wouldn't be meaningful.

I like the patches, I'd just prefer that they be sent in a separate
series so they can churn independently.