With the current cgroup namespace patches, the root dentry path of a mount as shown in /proc/self/mountinfo is the full global cgroup path. It is common for userspace to use /proc/self/mountinfo to search for cgroup mountpoints, and expect the root dentry path to relate to the cgroup paths in /proc/self/cgroup. Patch 2 in this set therefore virtualizes the root dentry path relative to the reader's cgroup namespace root.
Patch 1 fixes a bug in kernfs_path_from_node_locked() which is exposed by patch 2.
