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From:   Matthew Garrett <mjg59@google.com>
Date:   Mon, 12 Aug 2019 09:24:30 -0700
Message-ID: <CACdnJusGKAx-APuDi2+hqSSVXeeH5hBq4Chi-rPirDos4MvhgQ@mail.gmail.com>
Subject: Re: [Linux 5.2.x] /sys/kernel/debug/tracing/events/power/cpu_idle/id:
 BUG: kernel NULL pointer dereference, address: 0000000000000000
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Salvatore Bonaccorso <carnil@debian.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Paul Menzel <pmenzel@molgen.mpg.de>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Len Brown <lenb@kernel.org>, x86@kernel.org,
        LKML <linux-kernel@vger.kernel.org>, linux-pm@vger.kernel.org
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On Mon, Aug 12, 2019 at 8:29 AM Steven Rostedt <rostedt@goodmis.org> wrote:

> From what I understand, Matthew's "lockdown" work is to prevent the
> system from doing anything to see what is happening in the kernel. This
> includes tracefs. This looks like it is working as designed.

Oopsing the kernel isn't working as designed. Ben has a patch to fix this.