On Mon, Oct 01, 2018 at 04:11:27PM +1000, Dave Chinner wrote: > This reminds me so much of Linux mmap() in the mid-2000s - mmap() > worked for ext3 without being aware of page faults, so most mm/ > developers at the time were of the opinion that all the other > filesystems should work just fine without being aware of page > faults.
This is probably because RDMA was introduced around that time, before page_mkwrite was added.. It kind of sounds like page_mkwrite() broke all the writing get_user_pages users and it wasn't realized at the time. BTW, we are hosting a session on this at Plumbers during the RDMA track, hope everyone interested will be able to attend. Jason
