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Date:   Wed, 16 Feb 2022 09:58:50 +0100
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Subject: Re: [RFC V2 12/21] rv/reactor: Add the printk reactor
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To:     John Ogness <john.ogness@linutronix.de>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Steven Rostedt <rostedt@goodmis.org>
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        Catalin Marinas <catalin.marinas@arm.com>,
        Marco Elver <elver@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Gabriele Paoloni <gpaoloni@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Clark Williams <williams@redhat.com>,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-trace-devel@vger.kernel.org
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From:   Daniel Bristot de Oliveira <bristot@kernel.org>
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On 2/15/22 20:33, John Ogness wrote:
>> I saw deadlocks in the past, and while testing the WIP monitor some
>> time ago, it seems it depends on the console type. If such restriction
>> does not exist anymore, I can remove that comment, it would be even
>> better!
> If you say it depended on the console type, then it was probably the
> framebuffer console that was at fault. The fbcon is a landmine for
> deadlocks, which is why PREEMPT_RT avoids fbcon printing from
> non-preemptible context. For mainline, the series is currently in
> review.
> 
> Perhaps avoiding fbcon would be good enough for you to avoid deadlocks
> with this reactor using printk().

So, I will keep printk(), add a depends on *!* fbcon, and remove the comment.
What do you think?

-- Daniel