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Date:   Tue, 8 Oct 2019 15:48:31 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Petr Mladek <pmladek@suse.com>
Cc:     Qian Cai <cai@lca.pw>, Steven Rostedt <rostedt@goodmis.org>,
        sergey.senozhatsky.work@gmail.com, peterz@infradead.org,
        linux-mm@kvack.org, john.ogness@linutronix.de,
        akpm@linux-foundation.org, david@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] mm/page_isolation: fix a deadlock with printk()
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On Tue 08-10-19 15:42:56, Petr Mladek wrote:
[...]
> I am not -mm maintainer so I could not guarantee that a patch
> using printk_deferred() will get accepted. But it will have much
> bigger chance than the original patch.

I am not going to ack any such patch until it is clear what is the
actual problem. The disucssion in this thread boils down to point to
lockdep splats which are most likely false possitives and there is no
clear evidence that the is any actual deadlock as those would be clearly
identifiable if the zone->lock or any other spinlock spinlock were
participating.
-- 
Michal Hocko
SUSE Labs