Re: [PATCH v2] kcov: properly check if we are in an interrupt

From: Andrew Morton
Date: Mon Oct 10 2016 - 19:32:47 EST

On Mon, 10 Oct 2016 19:19:11 +0200 Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:

> On Mon, Oct 10, 2016 at 6:10 PM, Andrey Konovalov <andreyknvl@xxxxxxxxxx> 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@xxxxxxxxxx>
> Acked-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> 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?