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Date:   Mon, 30 Apr 2018 18:00:11 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Joel Fernandes <joelaf@google.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Tom Zanussi <tom.zanussi@linux.intel.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Boqun Feng <boqun.feng@gmail.com>,
        Paul McKenney <paulmck@linux.vnet.ibm.com>,
        "Cc: Frederic Weisbecker" <fweisbec@gmail.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Fenguang Wu <fengguang.wu@intel.com>,
        Baohong Liu <baohong.liu@intel.com>,
        Vedang Patel <vedang.patel@intel.com>,
        "Cc: Android Kernel" <kernel-team@android.com>
Subject: Re: [PATCH] softirq: reorder trace_softirqs_on to prevent lockdep
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On Mon, 30 Apr 2018 17:01:04 +0000
Joel Fernandes <joelaf@google.com> wrote:
Tried 4.17-rc3 and see it too. Could be difference in configs? Also, the
> environment is a Qemu system with single CPU 1GB memory. Attached is the
> config.
> 
> I think when I had multiple CPUs it was harder to trigger it, but can't
> really remember now. There was a time when triggering it was quite
> intermittent.
>

Bah, I didn't have CONFIG_DEBUG_LOCKDEP enabled, and that is what does
the backtrace.

-- Steve