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Date:   Mon, 29 Aug 2022 21:48:11 -0700
From:   Josh Poimboeuf <jpoimboe@kernel.org>
To:     David Laight <David.Laight@aculab.com>
Cc:     'Peter Zijlstra' <peterz@infradead.org>,
        Segher Boessenkool <segher@kernel.crashing.org>,
        Borislav Petkov <bp@alien8.de>, X86 ML <x86@kernel.org>,
        Michael Matz <matz@suse.de>,
        "linux-toolchains@vger.kernel.org" <linux-toolchains@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH] x86/sev: Mark snp_abort() noreturn
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On Thu, Aug 25, 2022 at 01:12:42PM +0000, David Laight wrote:
> ...
> > Objtool follows control flow. As you said above, noreturn functions
> > behave differently and code-gen after a call to a noreturn function
> > stops.
> 
> Thinks....
> 
> How near is objtool to outputting a list of functions and the
> stack offset at which they call something else?

It basically already does this.

> With the 'magic numbers' to track indirect jumps that is very
> nearly enough information to do full static stack depth checking.

What do you mean by 'magic numbers'?

-- 
Josh