Question about the userfaultfd write-protect support

(Add Zhanghailiang and Gonglei)

Hi Andrea,

We've implemented a demo of KVM live memory snapshot based on the userfaultfd write-protect series in your private tree(https://git.kernel.org/pub/scm/linux/kernel/git/andrea/aa.git/log/). We did a little hack on that series to make the demo works.

Zhang had discussed with you about this one or two years ago([1][2]), so do you have any plan to make this series upstream ? If you will, then what is the time schedule ? We really expect the userfaultfd write-protect series would be merged.

References:
[1] https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg00664.html
[2] https://lists.nongnu.org/archive/html/qemu-devel/2014-11/msg02891.html

Regards,
Longpeng(Mike)