Re: [PATCH] vfio/type1: Unpin zero pages

[Jason Gunthorpe]

On Tue, Aug 30, 2022 at 05:43:43PM +0200, David Hildenbrand wrote:

> I think one approach is mmap'ing a devdax device. To test without actual
> NVDIMM hardware, there are ways to simulate it even on bare metal using
> the "memmap=" kernel parameter.
> 
> https://nvdimm.wiki.kernel.org/
> 
> Alternatively, you can use an emulated nvdimm device under QEMU -- but
> then you'd have to run VFIO inside the VM. I know (that you know) that
> there are ways to get that working, but it certainly requires more effort :)
> 
> ... let me know if you need any tips&tricks.

currently pin_user_pages will not return ZONE_DEVICE pages anyhow, so
it is not relevant to this snippet

You might seem them on that follow_pfn flow though :\

Jason