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Date:   Wed, 21 Nov 2018 18:20:02 +0000
From:   Christopher Lameter <cl@linux.com>
To:     Nicolas Boichat <drinkcat@chromium.org>
cc:     Robin Murphy <robin.murphy@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Joerg Roedel <joro@8bytes.org>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Michal Hocko <mhocko@suse.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Levin Alexander <Alexander.Levin@microsoft.com>,
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        Mike Rapoport <rppt@linux.vnet.ibm.com>,
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        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Yong Wu <yong.wu@mediatek.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Tomasz Figa <tfiga@google.com>, yingjoe.chen@mediatek.com
Subject: Re: [PATCH v2 0/3] iommu/io-pgtable-arm-v7s: Use DMA32 zone for page
 tables
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On Sun, 11 Nov 2018, Nicolas Boichat wrote:

> This is a follow-up to the discussion in [1], to make sure that the page
> tables allocated by iommu/io-pgtable-arm-v7s are contained within 32-bit
> physical address space.

Page tables? This means you need a page frame? Why go through the slab
allocators?