On Fri, Jun 04, 2021 at 12:56:22PM -0700, Axel Rasmussen wrote:

Userfaultfd minor fault mode is supported starting from Linux 5.13.

This commit adds a description of the new mode, as well as the new ioctl
used to resolve such faults. The two go hand-in-hand: one can't resolve
a minor fault without continue, and continue can't be used to resolve
any other kind of fault.

This patch covers just the hugetlbfs implementation (in 5.13). Support
for shmem is forthcoming, but as it has not yet made it into a kernel
release candidate, it will be added in a future commit.

Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>

FWIW:

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu