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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 7 Mar 2019 08:33:26 -0800
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Subject: Re: [PATCH 18/20] objtool: Add UACCESS validation
To:     Peter Zijlstra <peterz@infradead.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>,
        Catalin Marinas <catalin.marinas@arm.com>,
        James Morse <james.morse@arm.com>, valentin.schneider@arm.com,
        Brian Gerst <brgerst@gmail.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        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>
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On Thu, Mar 7, 2019 at 3:52 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> XXX: are we sure we want __memset marked AC-safe?

It's certainly one of the safer functions to call with AC set, but it
sounds wrong anyway. It's not like it's likely to leak kernel data
(most memset's are with 0, and even the non-zero ones I can't imagine
are sensitive - more like poison values etc).

What's the call site that made you go "just add __memset() to the list"?

            Linus