I have a very basic doubt here ... what makes it impossible to sleep in an ISR? I mean, I know that the kernel preemption is disabled and the kernel will panic, but I could not understand why? TIA, LL - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs