On Thu, Jun 23, 2022 at 01:06:13AM +0800, Miaohe Lin wrote: > vma->vm_page_prot is read lockless from the rmap_walk, it may be updated > concurrently. Using READ_ONCE to prevent the risk of reading intermediate > values. Have you checked all other vm_page_prot reads that they hold mmap_lock? I think the right fix would be to provide a helper to read vm_page_prot which does READ_ONCE() and use it everywhere. This seems more sustainable. -- Kirill A. Shutemov
