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Date:   Sat, 26 Feb 2022 13:48:02 -0800
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com,
        andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org,
        ndesaulniers@google.com, keescook@chromium.org,
        samitolvanen@google.com, mark.rutland@arm.com,
        alyssa.milburn@intel.com
Subject: Re: [PATCH 21/29] objtool: Rename --duplicate to --lto
Message-ID: <20220226214802.4chmsrtstlerefmu@treble>
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 <20220218171409.814392411@infradead.org>
 <20220226194209.bvv3t65hhtnwltmk@treble>
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On Sat, Feb 26, 2022 at 11:42:13AM -0800, Josh Poimboeuf wrote:
> > +	OPT_BOOLEAN(0, "lto", &lto, "whole-archive like runs"),
> 
> "--lto" is a confusing name, since this "feature" isn't specific to LTO.
> 
> Also, it gives no indication of what it actually does.
> 
> What it does is, run objtool on vmlinux or module just like it's a
> normal object, and *don't* do noinstr validation.  Right?
> 
> It's weird for the noinstr-only-mode to be the default.
> 
> BTW "--duplicate" had similar problems...
> 
> So how about:
> 
> - Default to normal mode on vmlinux/module, i.e. validate and/or
>   generate ORC like any other object.  This default is more logically
>   consistent and makes sense for the future once we get around to
>   parallelizing objtool.
> 
> - Have "--noinstr", which does noinstr validation, in addition to all
>   the other objtool validation/generation.  So it's additive, like any
>   other cmdline option.  (Maybe this option isn't necessarily needed for
>   now.)

It just dawned on me that "--noinstr" already exists.  But I'm
scratching my head trying to figure out the difference between
"--noinstr" and omitting "--lto".

> - Have "--noinstr-only" which only does noinstr validation and nothing
>   else.  (Alternatively, "--noinstr --dry-run")
> 
> ?

-- 
Josh