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Did it ever actually work there :) Why not just skip them and > > call it a day :D > > I think QEMU just always sets MADV_MERGABLE and later activates uffd. So that > needs some care to not disable them. So let's rather try to get it fixed properly. > > Can you send out proper patches? Thanks! +1. Lance's direction is right. Unsharing is not an access: do_wp_page() already skips the uffd-wp fault on FAULT_FLAG_UNSHARE, and RWP should do the same. -- Kiryl Shutsemau / Kirill A. Shutemov