history is hard

[jim stephens]

On 5/30/2020 11:15 PM, Eric Smith via cctalk wrote:
> On 05/29/2020 02:38 PM, Noel Chiappa via cctalk wrote:
>>      <snip>
>> Low-level machines did not even have storage protection
>> keys, and on the /40 and /50 (I think) it was an option,
>> although I'd guess almost any /50 had it installed.
Our /50 had it and I have never seen any indication in the documentation 
for the hardware that
indicated that it was an option.

I don't think that either MVT or MFT would have been very stable without 
it.  I certainly spent a lot of time
studying how to get around it, and am responsible for a couple of SPIE 
patches in the MVT product
from exploits trying to get into supervisor mode to muck with such.

Yes, I know supervisor state isn't tied to the storage keys, but that 
was the way I went to
try to circumvent the storage keys.

thanks
Jim