alt Hacker NewsI believe that in some vehicles the backup camera actually runs on a separate (possibly real time, otherwise certainly heavily nice'ed) system. Tesla has a recall where they had to nice the backup camera software. The problem was if the display freezes or is delayed, then the driver is backing up and not aware that he doesn't see where he is going (he thinks that what he sees is representative of the area around the car currently).
In Hyundai and Renault I've seen it first hand that it's a separate subsystem that works even when the infotainment is dead/unresponsive/glitchy (it's like that probably everywhere, these two are just the sample I have).