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Date:   Wed, 15 Jan 2020 08:37:54 -0800
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Marco Elver <elver@google.com>
Cc:     Alexander Potapenko <glider@google.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Dmitriy Vyukov <dvyukov@google.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Qian Cai <cai@lca.pw>
Subject: Re: [PATCH -rcu] kcsan: Make KCSAN compatible with lockdep
Message-ID: <20200115163754.GA2935@paulmck-ThinkPad-P72>
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On Wed, Jan 15, 2020 at 05:26:55PM +0100, Marco Elver wrote:
> On Tue, 14 Jan 2020 at 18:24, Alexander Potapenko <glider@google.com> wrote:
> >
> > > --- a/kernel/kcsan/core.c
> > > +++ b/kernel/kcsan/core.c
> > > @@ -337,7 +337,7 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type)
> > >          *      detection point of view) to simply disable preemptions to ensure
> > >          *      as many tasks as possible run on other CPUs.
> > >          */
> > > -       local_irq_save(irq_flags);
> > > +       raw_local_irq_save(irq_flags);
> >
> > Please reflect the need to use raw_local_irq_save() in the comment.
> >
> > >
> > >         watchpoint = insert_watchpoint((unsigned long)ptr, size, is_write);
> > >         if (watchpoint == NULL) {
> > > @@ -429,7 +429,7 @@ kcsan_setup_watchpoint(const volatile void *ptr, size_t size, int type)
> > >
> > >         kcsan_counter_dec(KCSAN_COUNTER_USED_WATCHPOINTS);
> > >  out_unlock:
> > > -       local_irq_restore(irq_flags);
> > > +       raw_local_irq_restore(irq_flags);
> >
> > Ditto
> 
> Done. v2: http://lkml.kernel.org/r/20200115162512.70807-1-elver@google.com

Alexander and Qian, could you please let me know if this fixes things
up for you?

							Thanx, Paul