On Fri, Mar 27, 2009 at 12:37:07PM -0400, Mike Frysinger wrote: > there are processors which implement other features that people consider part > of the MMU (like protection). virtual memory is the most significant feature.
Sure. > lies. there are no serious limitations at all with FDPIC ELF. it is > functionality equivalent to ELFs running under a MMU. Well I haven't looked at FDPIC ELF since it doesn't work on m68knommu yet. > you cannot do fork() without virtual memory since both processes will have > pointers to the same addresses and there's no way to relocate them. OK, I suspected that was the case. > you can memory map files without a MMU How? > memory protection is not strictly part of the MMU. some processors implement > MPU's (like the Blackfin processor) and the kernel supports it just fine. > that gets you standard data/instruction rwx control. OK, I had never heard of it done that way before. That's neat. Certainly not typical of a nommu system though. -- Len Sorensen _______________________________________________ uClinux-dev mailing list [email protected] http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by [email protected] To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
