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Date:   Thu, 14 May 2020 15:50:25 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Marco Elver <elver@google.com>
Cc:     Will Deacon <will@kernel.org>,
        kasan-dev <kasan-dev@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v5 00/18] Rework READ_ONCE() to improve codegen
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On Thu, May 14, 2020 at 03:35:58PM +0200, Marco Elver wrote:
>   4. __no_kcsan functions should never be spuriously inlined into
> instrumented functions, causing the accesses of the __no_kcsan
> function to be instrumented. [Satisfied by Clang >= 7. All GCC
> versions are broken.]

The current noinstr annotation implies noinline, for a similar issue, we
need the function to be emitted in a specific section. So while yuck,
this is not an immediate issue for us.