Re: [PATCH 0/2] KVM: do not assume PTE is writable after follow_pfn

[Christoph Hellwig]

On Mon, Feb 08, 2021 at 07:26:25PM -0400, Jason Gunthorpe wrote:
> > > page_mkclean() has some technique to make the notifier have the right
> > > size without becoming entangled in the PTL locks..
> > 
> > Right.  I guess it's because dax doesn't have "struct page*" on the
> > back, so it
> 
> It doesn't? I thought DAX cases did?

File system DAX has a struct page, device DAX does not.  Which means
everything using iomap should have a page available, but i'm adding
Dan as he should know the details :)