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Message-ID: <1516652825.9521.64.camel@infradead.org>
Subject: Re: [v8,02/12] objtool: Allow alternatives to be ignored
From:   David Woodhouse <dwmw2@infradead.org>
To:     Guenter Roeck <linux@roeck-us.net>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        Andi Kleen <ak@linux.intel.com>, Paul Turner <pjt@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linux-foundation.org>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Dave Hansen <dave.hansen@intel.com>, tglx@linutronix.de,
        Kees Cook <keescook@google.com>,
        Rik van Riel <riel@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Jiri Kosina <jikos@kernel.org>, gnomes@lxorguk.ukuu.org.uk,
        x86@kernel.org, thomas.lendacky@amd.com
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Date:   Mon, 22 Jan 2018 20:27:05 +0000
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On Mon, 2018-01-22 at 12:25 -0800, Guenter Roeck wrote:
>=20
> It uses "-mindirect-branch=3Dthunk -mindirect-branch-loop=3Dpause
> -fno-jump-tables", though I don't know if that even exists in
> upstream gcc (it is the gcc use for Chrome OS builds). I'll pass
> your feedback to our compiler team.

We moved on from that and the upstream retpoline support in the kernel
won't recognise it.

> Either case, I think it is less than optimal that objtool crashes
> with _any_ object code.

Yeah, I'll give you that one :)
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