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Date: Mon, 10 Oct 2016 16:32:34 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>,
        Nicolai Stange <nicstange@gmail.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
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        Vegard Nossum <vegard.nossum@oracle.com>,
        Quentin Casasnovas <quentin.casasnovas@oracle.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>
Subject: Re: [PATCH v2] kcov: properly check if we are in an interrupt
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On Mon, 10 Oct 2016 19:19:11 +0200 Dmitry Vyukov <dvyukov@google.com> wrote:

> On Mon, Oct 10, 2016 at 6:10 PM, Andrey Konovalov <andreyknvl@google.com> wrote:
> > in_interrupt() returns a nonzero value when we are either in an
> > interrupt or have bh disabled via local_bh_disable(). Since we are
> > interested in only ignoring coverage from actual interrupts, do a
> > proper check instead of just calling in_interrupt().
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> 
> FWIW
> Acked-by: Dmitry Vyukov <dvyukov@google.com>
> 
> This fixes a very real problem for us.
> As per discussion in v1, other solution would involve auditing all
> uses of in_interrupt() which needs knowledge about all drivers.

OK, but I'm not seeing a description of what the problem *is*.  Could
we please have a complete description of the user-visible effects of this
change, for the changelog?