Don’t pay attention to the BONE_READY etc parts, or most of the via parts. (Via child of is important; via parent bone is important; via action is important.) That’s probably more for devs. Notice that each dependency is actually represented by two or three lines, only one of which is important. Just look at the names of the bones. If you made the rig yourself, it should be pretty obvious how each bone depends on the one listed.
For your example, the important thing to realize is that mch.pelvis.l depends on ctrl.thigh.l which depends on subctrl.pelvis.l, which in turn depends on mch.pelvis.l. There’s your dependency loop. You’re going to have to decide about which bone you want to drive the hierarchy: mch, ctrl, or subctrl. (I would suggest that bones named mch should depend on bones named subctrl, which in turn should depend on bones named ctrl. Ctrl bones shouldn’t depend on anything except other ctrl bones.)