`docker run -v /foo:/foo:ro` is now recursively read-only on kernel >= 5.12.
Automatically falls back to the legacy non-recursively read-only mount mode on kernel < 5.12.
Use `ro-non-recursive` to disable RRO.
Use `ro-force-recursive` or `rro` to explicitly enable RRO. (Fails on kernel < 5.12)
Fix issue 44978
Fix docker/for-linux issue 788
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
5045a2de24