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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 29 Aug 2016 08:36:46 -0700
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Subject: Re: [PATCH 2/2] mm/usercopy: enable usercopy size checking for modern
 versions of gcc
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
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        Andy Lutomirski <luto@amacapital.net>,
        Steven Rostedt <rostedt@goodmis.org>, Brian Gerst <brgerst@gmail.com>,
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        Byungchul Park <byungchul.park@lge.com>,
        Nilay Vaish <nilayvaish@gmail.com>
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On Mon, Aug 29, 2016 at 7:48 AM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
>
> So I *think* your patch fixes the wrong problem.  That's probably at
> least somewhat my fault because I misunderstood the issue before and may
> have described it wrong at some point.
>
> AFAICT, gcc isn't doing anything wrong, and the false positives are
> "intentional".
>
> There are in fact two static warnings (which are being silenced for new
> versions of gcc):

[ snip snip details ]

Ok.

Color me convinced, I never even looked at the two different cases, I
thought it was just one issue.

Let's just remove the spurious false positive warning then, in order
to re-instate the *actual* warning that right now is disabled entirely
due to the unrelated false positives.

Thanks for looking into this. Would you happen to also have a patch
that can be applied? Hint hint..

               Linus