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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net/mlx5e: Do not recycle pages from emergency
 reserve
Date: Mon, 23 Jan 2017 10:45:40 -0500 (EST)
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From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Mon, 23 Jan 2017 09:39:40 +0100

> BUT there are other advantages of using a guaranteed recycle pool
> facility (like the page_pool).  Namely, (1) DMA-overhead: keeping page
> DMA mapped to counter DMA+IOMMU overhead, (2) RX-zero-copy: opens up
> for a software memory model solution for pre-VMA-mapping pages to
> userspace (See: [1] for argument how this avoids leaking kernel mem,
> but only expose/leak packet-data mem)

+1