On Thu, Feb 04, 2021 at 08:59:59PM +0100, Daniel Vetter wrote: > So I think just checking for VM_PFNMAP after the vma is set up should > be enough to guarantee we'll only have pte_special ptes in there, > ever. But I'm not sure, this stuff all isn't really documented much > and the code is sometimes a maze (to me at least). Yes, that makes sense. VM_PFNMAP and !VM_MIXEDMAP seems like the right check after the VMA is populated But how do you stuff special pfns into a VMA outside the fault handler? Jason
