@dsmid: The bind mounts being mounted from the rootfs break mntroot's ro/rw detection, because it's only expecting a single line beginning with '/dev/root'

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Once the rootfs has been mounted rw, you won't be able to mount it back ro w/ mntroot, because it'll think it's already ro (while it's in fact catching the 'ro' from the bind mounts, which wins the test by virtue of coming last).