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Date:   Thu, 7 Mar 2019 21:23:19 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>, Peter Anvin <hpa@zytor.com>,
        Julien Thierry <julien.thierry@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andy Lutomirski <luto@amacapital.net>,
        Ingo Molnar <mingo@kernel.org>,
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        Brian Gerst <brgerst@gmail.com>,
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        Andrew Lutomirski <luto@kernel.org>,
        Borislav Petkov <bp@alien8.de>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH 18/20] objtool: Add UACCESS validation
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On Thu, Mar 07, 2019 at 07:48:13PM +0100, Peter Zijlstra wrote:
> Another thing I need to look at is why objtool only found memset_orig
> (from __memset) but not memset_erms, which if I read the code right, is
> a possible alternative there.

Turns out we only look for sibling calls in the original instruction
stream, not in any alternatives; which in general seems like a fair
enough assumption.