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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Peter Zijlstra' <peterz@infradead.org>,
        Segher Boessenkool <segher@kernel.crashing.org>
CC:     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
Thread-Topic: [PATCH] x86/sev: Mark snp_abort() noreturn
Thread-Index: AQHYuE2/3wA7Q5vXrk6DdQVA60XyvK2/lqOw
Date:   Thu, 25 Aug 2022 13:12:42 +0000
Message-ID: <ce56926842dc49ecb08ddb9d828590af@AcuMS.aculab.com>
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...
> 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?

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

Recursive calls are a problem - but they ought to be banned
in kernel anyway.

	David

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