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Date: Wed, 25 Jan 2017 15:35:32 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH] kasan: Respect /proc/sys/kernel/traceoff_on_warning
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On Wed, Jan 25, 2017 at 03:32:11PM +0100, Alexander Potapenko wrote:

> > @@ -300,6 +301,8 @@ void kasan_report(unsigned long addr, size_t size,
> >         if (likely(!kasan_report_enabled()))
> >                 return;
> >
> > +       disable_trace_on_warning();
> > +
> Who is going to enable tracing back after we're done?

The user..

> Note that KASAN errors are not fatal, and the first one may possibly
> occur quite early.

WARN*() isn't fatal either, and it does the same thing. Note that
traceoff_on_warning is default disabled. You have to explicitly request
this.