On Mon, Oct 12, 2020 at 02:14:07PM -0700, Dan Williams wrote: > > ZONE_DEVICE struct pages have an extra reference count that complicates the > > code for put_page() and several places in the kernel that need to check the > > reference count to see that a page is not being used (gup, compaction, > > migration, etc.). Clean up the code so the reference count doesn't need to > > be treated specially for device private pages, leaving DAX as still being > > a special case. > > Please no half-step to removing the special casing... Agreed. I really like where the refcount changes are heading, but I don't think this half-step is helpful.
