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From:   Logan Gunthorpe <logang@deltatee.com>
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Date:   Thu, 1 Mar 2018 14:45:09 -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 02:37 PM, Dan Williams wrote:
> Ah ok, I'd need to look at the details. I had been assuming that
> sparse-vmemmap could handle such a situation, but that could indeed be
> a broken assumption.

It handles it fine for many situations. But when you try to map 
something that is at the end of the physical address space then the 
spares-vmemmap needs virtual address space that's the size of the 
physical address space divided by PAGE_SIZE which may be a little bit 
too large...

Logan