Messages in this thread | | | From | Suren Baghdasaryan <> | Date | Tue, 1 Aug 2023 13:28:56 -0700 | Subject | Re: [PATCH 1/6] mm: enable page walking API to lock vmas during the walk |
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On Mon, Jul 31, 2023 at 1:24 PM Suren Baghdasaryan <surenb@google.com> wrote: > > On Mon, Jul 31, 2023 at 12:33 PM Linus Torvalds > <torvalds@linux-foundation.org> wrote: > > > > On Mon, 31 Jul 2023 at 12:31, Suren Baghdasaryan <surenb@google.com> wrote: > > > > > > I got the idea but a couple of modifications, if I may. > > > > Ack, sounds sane to me. > > Ok, I'll wait for more feedback today and will post an update tomorrow. Thanks!
I have the new patchset ready but I see 3 places where we walk the pages after mmap_write_lock() while *I think* we can tolerate concurrent page faults (don't need to lock the vmas):
s390_enable_sie() break_ksm() clear_refs_write()
In all these walks we lock PTL when modifying the page table entries, that's why I think we can skip locking the vma but maybe I'm missing something? Could someone please check these 3 cases and confirm or deny my claim? Thanks, Suren.
> > > > > Linus
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