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Date:   Fri, 17 Jan 2020 11:49:57 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Qian Cai <cai@lca.pw>
Cc:     akpm@linux-foundation.org, mhocko@kernel.org,
        sergey.senozhatsky.work@gmail.com, pmladek@suse.com,
        rostedt@goodmis.org, peterz@infradead.org, david@redhat.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Michal Hocko <mhocko@suse.com>
Subject: Re: [PATCH -next v4] mm/hotplug: silence a lockdep splat with
 printk()
Message-ID: <20200117024957.GA7372@google.com>
References: <20200117022111.18807-1-cai@lca.pw>
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On (20/01/16 21:21), Qian Cai wrote:
> It is not that hard to trigger lockdep splats by calling printk from
> under zone->lock. Most of them are false positives caused by lock chains
> introduced early in the boot process and they do not cause any real
> problems (although some of the early boot lock dependencies could
> happenn after boot as well). There are some console drivers which do
> allocate from the printk context as well and those should be fixed. In
> any case false positives are not that trivial to workaround and it is
> far from optimal to lose lockdep functionality for something that is a
> non-issue.
[..]
>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Signed-off-by: Qian Cai <cai@lca.pw>

FWIW,
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>

	-ss