On second thought, handle unknown faults caused by processes by sending
SIGSEGV to them instead of bringing the whole system to a grind.
arm/archconst: use values defined in armreg.h
Change-Id: Ieed5bb06910ab0c8eef1e68b0b4eec680867acd3
For now, distinguish alignment, translation and permission faults.
The first kind of faults cause the kernel to send SIGBUS to the
process causing the fault, the latter two are forwarded to `vm' as
pagefaults. Previously, any data abort was forwarded to `vm' as
a pagefault, resulting in hard to debug issue #104.
Any unhandled fault status results in a disaster. This seems
better than naively hoping `vm' can do something about it.
Change-Id: I526f575bb2681e087e20fd49c5c0846cdd450c31