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SubjectRe: [PATCH v7 2/8] iov_iter: Add a function to extract a page list from an iterator
Date
David Hildenbrand <david@redhat.com> 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

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