"Like, you use an interrupt as an..." <- If I may chime in, the main reason which "deterred" me from enabling an irq on both core while keeping the same handler is that the handler will need to clear the irq flag. The silicon may handle that case gracefully or not. Adding an if in the handler to only let 1 core do the clearing kind of defeated the point of "same handler". there was for me other(simpler solutions) with wife/sev.