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Date:   Mon, 22 Aug 2022 13:14:47 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Michal Hocko <mhocko@suse.com>
Cc:     Christoph Hellwig <hch@lst.de>, iommu@lists.linux.dev,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Robin Murphy <robin.murphy@arm.com>,
        David Rientjes <rientjes@google.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] dma-pool: limit DMA and DMA32 zone size pools
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On Mon, Aug 22, 2022 at 10:41:01AM +0200, Michal Hocko wrote:
> ZONE_DMA existance is not runtime controlable (at least on x86).

This is more about ZONE_DMA32 that can disappear if all memory is
inside ZONE_DMA.  That is highly unusual (but still possible) with a
tiny x86-style ZONE_DMA, but can happen with a larger one other
architectures.