David Hildenbrand <david@xxxxxxxxxx> wrote: > How does this work align with the goal of no longer using FOLL_GET for > O_DIRECT? We should get rid of any FOLL_GET usage for accessing page content. Would that run the risk of changes being made by the child being visible to the a DIO write if the parent changes the buffer first? PARENT CHILD ====== ===== start-DIO-write fork() = pid fork() = 0 alter-buffer CoW happens page copied original page retained alter-buffer <DMA-happens> David