Comment 4 for bug 1655842

you could also try cherry-picking https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=6b4e3181d7bd5ca5ab6f45929e4a5ffa7ab4ab7f , but that will probably need some more inbetween patches as well..

reverting the two commits fixed the issue for our users (Proxmox VE, which uses a kernel based on the 4.4.x one from 16.04)