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Date:   Mon, 14 Aug 2023 12:56:36 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Josh Poimboeuf <jpoimboe@kernel.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, David.Kaplan@amd.com,
        Andrew.Cooper3@citrix.com, gregkh@linuxfoundation.org
Subject: Re: [RFC][PATCH 06/17] x86/cpu: Add SRSO untrain to retbleed=
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On Sat, Aug 12, 2023 at 02:10:34PM +0200, Borislav Petkov wrote:
> On Sat, Aug 12, 2023 at 01:24:04PM +0200, Peter Zijlstra wrote:
> > That very experience wants me to avoid doing it again :-/ But you all
> > really want to keep the parameter, can we at least rename it something
> > you can remember how to type, like 'srso=' instead of this horrific
> > 'spec_rstack_overflow=' thing?
> 
> I'm all for short'n'sweet but last time I did that, Linus said we should
> have option names which aren't abbreviations which don't mean anything.

So:

 1) do you guys really want to keep this extra argument?

 2) if so, can we *PLEASE* rename it, because the current naming *SUCKS*.


I really don't see the need for an extra feature, we can trivially fold
the whole thing into retbleed, that's already 2 issues, might as well
make it 3 :-)


If we're going to rename, how about we simply call it 'inception' then
we haz both 'retbleed=' and 'inception=' and we're consistent here. Then
I'll make a compromise and do:

 's/zen_\(untrain_ret\|return_thunk\)/btc_\1/g'

so that the actual mitigations have the official amd name on them --
however much I disagree with calling this branch-type-confusion.