On Mon, May 22, 2017 at 12:44:14PM +0000, Avri Altman wrote: > Those debugfs entries are there for ages, and there are some user-space utilities, > e.g. for benchmarking etc. that count on it being there, > as the key identification criteria if a mmc device is present. debugfs is an optional feature not present on many systems, and explicitly not considered a kernel ABI.