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Date:   Tue, 19 May 2020 17:09:58 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Andrey Konovalov <andreyknvl@google.com>
Cc:     Marco Elver <elver@google.com>, Dmitry Vyukov <dvyukov@google.com>,
        Alexander Potapenko <glider@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Linux Memory Management List <linux-mm@kvack.org>,
        kernel test robot <rong.a.chen@intel.com>
Subject: Re: [PATCH] kasan: Disable branch tracing for core runtime
Message-Id: <20200519170958.d6e399f7f98286c1162f1383@linux-foundation.org>
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        <CAAeHK+wcrmo=Hhwvqzd8kC-=5UR+fzRcA_4mo8wccWCTdrEzEQ@mail.gmail.com>
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On Tue, 19 May 2020 23:05:46 +0200 Andrey Konovalov <andreyknvl@google.com> wrote:

> On Tue, May 19, 2020 at 8:25 PM Marco Elver <elver@google.com> wrote:
> >
> > During early boot, while KASAN is not yet initialized, it is possible to
> > enter reporting code-path and end up in kasan_report(). While
> > uninitialized, the branch there prevents generating any reports,
> > however, under certain circumstances when branches are being traced
> > (TRACE_BRANCH_PROFILING), we may recurse deep enough to cause kernel
> > reboots without warning.
> >
> > To prevent similar issues in future, we should disable branch tracing
> > for the core runtime.
> >
> 
> ...
>
> Reviewed-by: Andrey Konovalov <andreyknvl@google.com>

Thanks, I queued this for 5.7.