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Date: Fri, 29 May 2015 13:50:45 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Petr Mladek <pmladek@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Dave Anderson <anderson@redhat.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Kay Sievers <kay@vrfy.org>, Jiri Kosina <jkosina@suse.cz>,
        Michal Hocko <mhocko@suse.cz>, Jan Kara <jack@suse.cz>,
        linux-kernel@vger.kernel.org, Wang Long <long.wanglong@huawei.com>,
        peifeiyue@huawei.com, dzickus@redhat.com, morgan.wang@huawei.com,
        sasha.levin@oracle.com
Subject: Re: [PATCH 00/10] printk: Avoid deadlock in NMI + vprintk_emit()
 cleanup
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On Mon, 25 May 2015 14:46:23 +0200 Petr Mladek <pmladek@suse.cz> wrote:

> The main source of deadlocks caused by printk() in NMI context has been
> solved by the commit a9edc88093287 ("x86/nmi: Perform a safe NMI stack
> trace on all CPUs").
> 
> But there are still few warnings printed in the NMI code that could
> case a deadlock. For example, see the freeze discussed at
> https://lkml.org/lkml/2015/5/20/481

I'm not (yet) convinced that we want the entire patchset btw.  Do we
really want to try to semi-support printk from NMI?  With a rather
nasty set of hacks?

Why not just delete the offending printks?