PSA address range x'800' thru x'FFF' are intended to be key0 fetch protected and as ISRDDN is just a normal problem state (key8) program it will not be able to reference that memory.
I was under the impression that it has been this way "for a while". Rob Scott Rocket Software ________________________________ From: IBM Mainframe Discussion List <[email protected]> on behalf of Philippe Leite <[email protected]> Sent: 01 August 2025 3:40 PM To: [email protected] <[email protected]> Subject: Re: Strange S0C4 on z15 EXTERNAL EMAIL Interestingly, I am experiencing the same situation here. In an LPAR running z/OS 3.1 on a z14, when I send the command “TSO ISRDDN B 800.”, I can view the contents of PSA 2048-4095. But when I am in another LPAR with the same z/OS 3.1 on a z15, the same command “TSO ISRDDN B 800.” shows me an error message “Storage unavailable.” Philippe Leite z/OS System Programmer ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ================================ Rocket Software, Inc. and subsidiaries ¦ 77 Fourth Avenue, Waltham MA 02451 ¦ Main Office Toll Free Number: +1 855.577.4323 Contact Customer Support: https://my.rocketsoftware.com/RocketCommunity/RCEmailSupport Unsubscribe from Marketing Messages/Manage Your Subscription Preferences - http://www.rocketsoftware.com/manage-your-email-preferences Privacy Policy - http://www.rocketsoftware.com/company/legal/privacy-policy ================================ This communication and any attachments may contain confidential information of Rocket Software, Inc. All unauthorized use, disclosure or distribution is prohibited. If you are not the intended recipient, please notify Rocket Software immediately and destroy all copies of this communication. Thank you. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
