> From: Alex Williamson <alex.williamson@xxxxxxxxxx> > Sent: Friday, March 1, 2024 6:36 AM > > This reverts commit 873aefb376bbc0ed1dd2381ea1d6ec88106fdbd4. > > This was a heinous workaround and it turns out it's been fixed in mm > twice since it was introduced. Most recently, commit c8070b787519 > ("mm: Don't pin ZERO_PAGE in pin_user_pages()") would have prevented > running up the zeropage refcount, but even before that commit > 84209e87c696 ("mm/gup: reliable R/O long-term pinning in COW mappings") > avoids the vfio use case from pinning the zeropage at all, instead > replacing it with exclusive anonymous pages. > > Remove this now useless overhead. > > Suggested-by: David Hildenbrand <david@xxxxxxxxxx> > Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>