Changes since v1: - Further compile tests indicated a missing #define for rt_mutex_lock with lockdep enabled, so that one is added. - I have verified that I don't get any lockdep splat for a local i2c-mux setup with these patches applied, and that I do without them. Again, thanks for the report! Cheers, Peter Peter Rosin (2): rtmutex: allow specifying a subclass for nested locking i2c: mux: annotate the nested rt_mutex usage drivers/i2c/i2c-core-base.c | 2 +- drivers/i2c/i2c-mux.c | 4 ++-- include/linux/rtmutex.h | 7 +++++++ kernel/locking/rtmutex.c | 29 +++++++++++++++++++++++++---- 4 files changed, 35 insertions(+), 7 deletions(-) -- 2.11.0