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From:   Logan Gunthorpe <logang@deltatee.com>
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Date:   Thu, 1 Mar 2018 14:11:34 -0700
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Subject: Re: [PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory
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On 01/03/18 02:03 PM, Benjamin Herrenschmidt wrote:
> However, what happens if anything calls page_address() on them ? Some
> DMA ops do that for example, or some devices might ...

Although we could probably work around it with some pain, we rely on 
page_address() and virt_to_phys(), etc to work on these pages. So on 
x86, yes, it makes it into the linear mapping.

Logan