[PATCH v4 5/6] add listmount(2) syscall

[Christian Brauner]

> NOTE! ENTIRELY untested, but that naming and lack of argument sanity

Thanks for catching that. I've slightly tweaked the attached patch and
put it into vfs.fixes at [1]. There's a fsnotify performance regression
fix for io_uring in there as well. I plan to get both to you Saturday
CET. Let us know if there's any additional issues.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/log/?h=vfs.fixes