On Tue, 20 Apr 2021, Axel Rasmussen wrote:
This patch allows shmem-backed VMAs to be registered for minor faults. Minor faults are appropriately relayed to userspace in the fault path, for VMAs with the relevant flag.
This commit doesn't hook up the UFFDIO_CONTINUE ioctl for shmem-backed minor faults, though, so userspace doesn't yet have a way to resolve such faults.
Acked-by: Peter Xu peterx@redhat.com Signed-off-by: Axel Rasmussen axelrasmussen@google.com
And if this "04/10" had been numbered 03/10, I would have said Acked-by: Hugh Dickins hughd@google.com
Just read the comment above: "so userspace doesn't yet have a way to resolve such faults" - if it doesn't by this stage, we're in trouble.
fs/userfaultfd.c | 6 +++--- include/uapi/linux/userfaultfd.h | 7 ++++++- mm/memory.c | 8 +++++--- mm/shmem.c | 12 +++++++++++- 4 files changed, 25 insertions(+), 8 deletions(-)