Quoth Larry Baker: > Yes, this is indeed what can happen on a system like uClinux that does > not have an MMU (memory management unit). The tiny controller chips > that uClinux targets do not protect any part of the memory from being > accidentally corrupted. As long as the memory being accessed exists, > there is no hardware fence between a user program and the rest of memory.
It's especially fun when address 0 is valid memory (which is not uncommon). Then you don't get crashes from null pointer accesses, which most developers expect (and some can be lazy about protecting against, thinking that they'll find it during debugging). I always try to configure the target device's memory map such that addresses near 0 remain invalid, whenever possible -- but some targets don't support that. _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
