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Date: Mon, 26 Nov 2018 09:16:08 +0100
From: Michal Hocko <mhocko@suse.com>
Subject: Re: [PATCH] mm, hotplug: protect nr_zones with pgdat_resize_lock()
Message-ID: <20181126081608.GE12455@dhcp22.suse.cz>
References: <20181120014822.27968-1-richard.weiyang@gmail.com>
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To: Wei Yang <richard.weiyang@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>, Andrew Morton <akpm@linux-foundation.org>, Linux-MM <linux-mm@kvack.org>

On Mon 26-11-18 10:28:40, Wei Yang wrote:
[...]
> But I get some difficulty to understand this TODO. You want to get rid of
> these lock? While these locks seem necessary to protect those data of
> pgdat/zone. Would you mind sharing more on this statement?

Why do we need this lock to be irqsave? Is there any caller that uses
the lock from the IRQ context?
-- 
Michal Hocko
SUSE Labs