To close the loop on this, it seems pretty clear that any SVC form of MODESET (MODE= and/or KEY=), if the exit condition from the SVC is problem state, resets the PKM in CR3 to the settings quoted below. There is no way to get KEY=ZERO, problem state, while retaining the ability to issue SPKA X'x0'(0), where x is the original program storage key, typically 8 but possibly A through F.
The functioning is a little illogical IMHO, the documentation is misleading IMHO, but there's little question that this is the way that it works. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Charles Mills Sent: Tuesday, December 13, 2016 10:39 AM To: [email protected] Subject: Re: Question on SPKA and Control Register 3 I think it is in a less than ideal spot in the text. It appears to apply to the SVC form of MODESET in general, not just to the use of the MODE= parameter. I believe I am seeing that MODESET KEY=ZERO, in problem state, sets off the "other" bits in the PKM. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Tom Marchant Sent: Tuesday, December 13, 2016 10:28 AM To: [email protected] Subject: Re: Question on SPKA and Control Register 3 On Mon, 12 Dec 2016 22:04:45 -0500, Jim Mulder wrote: > The MODESET documentation says: > >,MODE=PROB, > MODE=SUP > Specifies that the PSW problem state indicator (bit 15) is to be >either turned on (PROB) or turned off (SUP). If the MODESET operation >completes with a problem state PSW, the caller?s PSW key mask (PKM) is >set according to the following rules: > >?The bit matching the resulting PSW key is set on. >?The bit matching key 9 is set on. >?For a task attached with ATTACHX using the KEY=NINE parameter, the >bits that were on in the PKM of the ATTACHX issuer are set on. >?All other bits are set off. > >If the resulting PSW is in supervisor state, the caller?s PKM is >unchanged. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
