CVE-2026-63950 mm/rmap: initialize nr_pages to 1 at loop start in try_to_unmap_one

In the Linux kernel, the following vulnerability has been resolved: mm/rmap: initialize nrpages to 1 at loop start in trytounmapone Initialize nrpages to 1 at the start of each loop iteration, like folioreferencedone does. Without this, nrpages computed by a previous foliounmapptebatch call can b...