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Date: Mon, 5 Oct 2015 13:18:18 +0200
From: Borislav Petkov <bp@alien8.de>
To: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        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>,
        Denys Vlasenko <dvlasenk@redhat.com>, Andi Kleen <ak@linux.intel.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Sasha Levin <sasha.levin@oracle.com>,
        Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Subject: Re: [PATCH] x86/process: Silence KASAN warnings in get_wchan()
Message-ID: <20151005111818.GA25898@nazgul.tnic>
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On Mon, Oct 05, 2015 at 01:28:26PM +0300, Andrey Ryabinin wrote:
> get_wchan() is racy by design, it may access volatile stack
> of running task, thus it may access redzone in a stack frame
> and cause KASAN to warn about this.
> 
> Use kasan_disable_current()/kasan_enable_current() to silence
> these warnings.

So we're going to be sprinkling those around code which kasan doesn't
like? Can't we do better, without touching all code everywhere?

Probably not but let me ask that just in case...

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
--