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Date:   Thu, 18 Jul 2019 17:57:04 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Leonardo Bras <leonardo@linux.ibm.com>
Cc:     Oscar Salvador <osalvador@suse.de>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Rapoport <rppt@linux.ibm.com>,
        Pavel Tatashin <pasha.tatashin@oracle.com>,
        =?iso-8859-1?B?Suly9G1l?= Glisse <jglisse@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Pasha Tatashin <Pavel.Tatashin@microsoft.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Subject: Re: [PATCH 1/1] mm/memory_hotplug: Adds option to hot-add memory in
 ZONE_MOVABLE
Message-ID: <20190718155704.GD30461@dhcp22.suse.cz>
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On Thu 18-07-19 12:50:29, Leonardo Bras wrote:
> On Thu, 2019-07-18 at 08:12 +0200, Oscar Salvador wrote:
> > We do already have "movable_node" boot option, which exactly has that
> > effect.
> > Any hotplugged range will be placed in ZONE_MOVABLE.
> Oh, I was not aware of it.
> 
> > Why do we need yet another option to achieve the same? Was not that
> > enough for your case?
> Well, another use of this config could be doing this boot option a
> default on any given kernel. 
> But in the above case I agree it would be wiser to add the code on
> movable_node_is_enabled() directly, and not where I did put.
> 
> What do you think about it?

No further config options please. We do have means a more flexible way
to achieve movable node onlining so let's use it. Or could you be more
specific about cases which cannot use the command line option and really
need a config option to workaround that?
-- 
Michal Hocko
SUSE Labs