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Date:   Mon, 11 Jul 2022 08:01:32 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Li Chen <me@linux.beauty>
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
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Subject: Re: [PATCH 0/4] add struct page and Direct I/O support to reserved
 memory
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Who is going to use it and how?  Because normally the reserved memory
is used through the DMA allocator, and you can't just do direct I/O
to that.