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Date:   Tue, 21 Apr 2020 18:02:34 -0700
From:   Roman Gushchin <guro@fb.com>
To:     Christoph Hellwig <hch@infradead.org>
CC:     <js1304@gmail.com>, Andrew Morton <akpm@linux-foundation.org>,
        <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Laura Abbott <labbott@redhat.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Michal Hocko <mhocko@suse.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Minchan Kim <minchan@kernel.org>,
        Rik van Riel <riel@surriel.com>,
        Christian Koenig <christian.koenig@amd.com>,
        Huang Rui <ray.huang@amd.com>,
        Eric Biederman <ebiederm@xmission.com>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Pavel Machek <pavel@ucw.cz>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: Re: [PATCH 01/10] mm/page-flags: introduce PageHighMemZone()
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On Tue, Apr 21, 2020 at 02:00:05AM -0700, Christoph Hellwig wrote:
> I don't think the names are very good.  I'd keep PageHighMem for the
> existing highmem zone, and add something like PageDirectMapped or
> similar for ay page that has a valid direct mapping address.  This will
> also come in handy if we plan to go ahead with the xpfo work.
> 

I agree. It also looks like the only remaining place with PageHighMem()
is using "if (!PageHighMem(page))", so "if (PageDirectlyMapped(page))" would be
even better.

Joonsoo, the series in general looks very good to me. Please, feel free
to add "Acked-by: Roman Gushchin <guro@fb.com>".

Thanks!