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* Only MAP_PRIVATE | MAP_ANONYMOUS will be supported in the 1st version due to kernel constraints.
* Only MAP_PRIVATE | MAP_ANONYMOUS will be supported in the 1st version due to kernel constraints.
* Userfault is known not to map one page into two places. Thus -- COW-ed pages will get COW-ed.
* Userfault is known not to map one page into two places. Thus -- COW-ed pages will get COW-ed.
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* Andrea (author) states that UFFDIO_REMAP might be slow as compared to UUFDIO_COPY. Probably it makes sense to copy data into tasks, not move.
+
* Andrea (author) states that UFFDIO_REMAP might be slow as compared to UFFDIO_COPY. Probably it makes sense to copy data into tasks, not move.
* Unmaps and mremaps can screw things up. Either we have to make uffd-s per VMA or add events about such things.
* Unmaps and mremaps can screw things up. Either we have to make uffd-s per VMA or add events about such things.
* Forks are even worse -- kid will just populate its memory with zero pages :(
* Forks are even worse -- kid will just populate its memory with zero pages :(