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Date: Mon, 5 Oct 2015 09:39:06 -0700
From: Andi Kleen <ak@linux.intel.com>
To: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>, Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, "x86@kernel.org" <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Andrey Konovalov <andreyknvl@google.com>,
        Kostya Serebryany <kcc@google.com>,
        Alexander Potapenko <glider@google.com>,
        kasan-dev <kasan-dev@googlegroups.com>, Borislav Petkov <bp@alien8.de>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Sasha Levin <sasha.levin@oracle.com>,
        Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] x86/process: Silence KASAN warnings in get_wchan()
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> But, I think I have the solution.
> We could have some blacklist - list of function names which we should be ignored.
> In kasan_report() we could resolve return address to function name and compare it with name in list.
> If name in list -> ignore report.

I think annotating statements is cleaner than functions, even if it
is more code. Much better documentation

But if you really want to annotate on the function level:

It's better to annotate the function directly than some hidden away list.
This way there is some indication that there are races in there, which is
generally useful documentation.

__racy_function or similar.

Also central lists are generally annoying as they cause patch conflicts.

If disabling with an attribute doesn't work, you could put it into a special section
with __attribute__((section ...)) and check the start/end symbol before reporting. 
That's how kprobes solves similar issues. It also has the advantage
that it stops inlining.

-Andi