Re: [PATCH] mm/x86/pat: Only untrack the pfn range if unmap region

[Jason Gunthorpe]

On Wed, Jul 17, 2024 at 12:30:19PM -0400, Peter Xu wrote:
> On Wed, Jul 17, 2024 at 04:17:12PM +0200, David Hildenbrand wrote:
> > I'd be curious how a previous truncation on a file can tear down a PFNMAP
> > mapping -- and if there are simple ways to forbid that (if possible).
> 
> Unfortunately, forbiding it may not work for vfio, as vfio would like to
> allow none (or partial) mapping on the bars.. at least so far that's the
> plan.

vfio doesn't support truncation? Or does that means something else
here?

Jason