Messages in this thread | | | Date | Wed, 1 Feb 2017 08:37:48 +0200 | From | Mike Rapoport <> | Subject | Re: [PATCH v2 2/5] userfaultfd: non-cooperative: add event for memory unmaps |
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On Tue, Jan 31, 2017 at 04:39:28PM -0800, Andrew Morton wrote: > On Fri, 27 Jan 2017 20:44:30 +0200 Mike Rapoport <rppt@linux.vnet.ibm.com> wrote: > > > When a non-cooperative userfaultfd monitor copies pages in the background, > > it may encounter regions that were already unmapped. Addition of > > UFFD_EVENT_UNMAP allows the uffd monitor to track precisely changes in the > > virtual memory layout. > > > > Since there might be different uffd contexts for the affected VMAs, we > > first should create a temporary representation for the unmap event for each > > uffd context and then notify them one by one to the appropriate userfault > > file descriptors. > > > > The event notification occurs after the mmap_sem has been released. > > I was going to bug you about not updating > Documentation/vm/userfaultfd.txt but the UFFD_FEATURE flags aren't > documented?
I'm going to send the documentation update in the next few days.
-- Sincerely yours, Mike.
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