Messages in this thread | | | From | Linus Torvalds <> | Date | Wed, 22 Dec 2021 10:40:18 -0800 | Subject | Re: [PATCH v1 06/11] mm: support GUP-triggered unsharing via FAULT_FLAG_UNSHARE (!hugetlb) |
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On Wed, Dec 22, 2021 at 8:08 AM Jan Kara <jack@suse.cz> wrote: > > Well, but O_DIRECT reads must use FOLL_PIN in any case because they modify > page data (and so we need to detect them both for COW and filesystem needs).
Well, O_DIRECT reads do, but not necessarily writes.
And hey, even reads have been dodgy in the past when we didn't really have the pinning logic - there's been a lot of users that just wanted it to work for their particular use-case rather than in general and in all situations..
Linus
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