Not really. Supervisor state is virtualized for the CMS user. When an instruction requiring supervisor state is executed in a CMS machine, a privop occurs and CP is given control to simulate the privileged instruction.?
On Sat, Nov 19, 2022, 3:51 PM Aaron Finerman <arfinerman@...> wrote:
When you run under VM, you are in a virtual machine and everything is virtualized. No one on this forum needs a lesson on that. Applications running under CMS? are given control in supervisor?state by default. If the problem state bit in the PSW is off, you are in supervisor state. There is no virtualized?supervisor state in any architecture.?
Best regards,??
On Sat, Nov 19, 2022 at 2:56 PM Fish Fish <david.b.trout@...> wrote:
Aaron Finerman wrote:
> To the best my knowledge, CMS always runs in supervisor state.
> But it does not run with key zero.
Then your knowledge needs updating. ;-)
CMS *thinks* it is running in supervisor state, but it actually doesn't. It simply runs in *virtualized* supervisor state. It *actually* in reality runs in problem state. All VM guests do. Only CP itself runs in real supervisor state, and then only when it actually needs to of course.
But I'm guessing you probably already knew that? Yes?
--
"Fish" (David B. Trout)
Software Development Laboratories
