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

From: David Hildenbrand
Date: Wed Jul 17 2024 - 12:32:43 EST


On 17.07.24 18:30, 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.

I think vfio should handle that memtype reservation manually, as you proposed. So that shouldn't block that IIUC.

--
Cheers,

David / dhildenb