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

From: Logan Gunthorpe
Date: Thu Mar 01 2018 - 16:45:36 EST




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