Messages in this thread | | | From | Suren Baghdasaryan <> | Date | Mon, 23 Oct 2023 12:01:32 -0700 | Subject | Re: [PATCH v3 2/3] userfaultfd: UFFDIO_MOVE uABI |
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On Mon, Oct 23, 2023 at 11:37 AM Peter Xu <peterx@redhat.com> wrote: > > On Mon, Oct 23, 2023 at 10:43:49AM -0700, Suren Baghdasaryan wrote: > > > Maybe we should follow what it does with mremap()? Then your current code > > > is fine. Maybe that's the better start. > > > > I think that was the original intention, basically treating remapping > > as a write operation. Maybe I should add a comment here to make it > > more clear? > > Please avoid mention "emulate as a write" - this is not a write, e.g., we > move a swap entry over without faulting in the page. We also keep the page > states, e.g. on hotness. A write will change all of that.
Understood.
> > Now rethinking with the recently merged WP_ASYNC: we ignore uffd-wp, which > means dirty from uffd-wp async tracking POV, that matches with soft-dirty > always set. Looks all good. > > Perhaps something like "Follow mremap() behavior; ignore uffd-wp for now" > should work?
Sounds good. Will add in the next version. Thanks!
> > -- > Peter Xu >
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