[PATCH v2 00/10] Copy Offload in NVMe Fabrics with P2P PCI Memory

[Logan Gunthorpe]

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