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From: Andrey Ryabinin <aryabinin@virtuozzo.com>
To: <linux-kernel@vger.kernel.org>
CC: Andrey Ryabinin <aryabinin@virtuozzo.com>, Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>,
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        Alexander Potapenko <glider@google.com>,
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        Denys Vlasenko <dvlasenk@redhat.com>, Andi Kleen <ak@linux.intel.com>,
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        Sasha Levin <sasha.levin@oracle.com>,
        Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Subject: [PATCH v2 0/2] Silence KASAN warnings in get_wchan()
Date: Tue, 13 Oct 2015 15:35:48 +0300
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Originally I suggested to implement READ_ONCE_NOCHECK(), like this:
#define READ_ONCE_NOCHECK(x) \
{(	typeof(x) __val; \
	kasan_disable_local(); \
	__val = READ_ONCE(x); \
	kasan_enable_local(); \
	__val;\
)}

But then I realised that we can't put this into linux/compiler.h
since it requires to add some includes (we need linux/kasan.h which
also requires linux/sched.h). It's not even that simple to put this into kernel.h

So I've come to another approach, see the first patch for details.
Pros:
 - It generates more efficient code rather than variant above
Cons:
 - REAS_ONCE() becomes rather messy.


Andrey Ryabinin (2):
  Provide READ_ONCE_NOCHECK()
  x86/process: Silence KASAN warnings in get_wchan()

 arch/x86/kernel/process.c    |  6 +++---
 include/linux/compiler-gcc.h | 13 ++++++++++++
 include/linux/compiler.h     | 49 ++++++++++++++++++++++++++++++++------------
 3 files changed, 52 insertions(+), 16 deletions(-)

-- 
2.4.9