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Aucbvax.4332 net.2bsd-bugs utzoo!decvax!ucbvax!dist2 Thu Oct 8 19:17:22 1981 kernels with more than 56K of instruction space I could not get a kernel with an instruction space bigger than 56K in size to load, even though we are running on a 11/70 which has split I/D. It appears that the last kernel I space mapping register was getting set to point to the I/O page regardless of the fact the we were running split I/D.

This is true and there is a very good reason for it to be done that way. If one loads a 407 or 430 file rather than a 411 one, the boot program (kernel/src/cmd/standalone/bootstrap/boot.c) will unseparate the kernel. If KISA7 is not pointing to the I/O page, there will be no way to access it (and no way to correct the mistake since all memory management registers sit in that page). Remember that in nonseparate mode, all fetches go through instruction space.

Carl

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