Early on the OP said that program that were OK before (I assume meaning that they passed testing) were now (with z/OS 2.5) not OK, but not abending. He had evidently tracked enough errors to accessing page 0 instead of their intended target that he's worried there are more.
This is not unique to assembler, although it may be in the OP's case. I've written COBOL and REXX programs to chase pointers to find control blocks. If I don't check that my pointers are non-zero, I could have the same type of errors. And these programs are not production programs, so failures are inconvenient, not catastrophic. Gary Weinhold Senior Application Architect DATAKINETICS | Data Performance & Optimization Phone:+1.613.523.5500 x216 Email: weinh...@dkl.com Visit us online at www.DKL.com E-mail Notification: The information contained in this email and any attachments is confidential and may be subject to copyright or other intellectual property protection. If you are not the intended recipient, you are not authorized to use or disclose this information, and we request that you notify us by reply mail or telephone and delete the original message from your mail system. ________________________________ From: IBM Mainframe Assembler List <ASSEMBLER-LIST@LISTSERV.UGA.EDU> on behalf of Retired Mainframer <00000fdaa76f2a18-dmarc-requ...@listserv.uga.edu> Sent: March 27, 2023 21:21 To: ASSEMBLER-LIST@LISTSERV.UGA.EDU <ASSEMBLER-LIST@LISTSERV.UGA.EDU> Subject: Re: Blocking Low core access from Assembler programs You are asking how to implement a solution but you have not told us what problem you are trying to solve. What is the real issue with this program accessing data in page 0? -----Original Message----- From: IBM Mainframe Assembler List <ASSEMBLER-LIST@LISTSERV.UGA.EDU> On Behalf Of syama prasad Sent: Monday, March 27, 2023 3:48 PM To: ASSEMBLER-LIST@LISTSERV.UGA.EDU Subject: Blocking Low core access from Assembler programs Hi, Is it possible to force an Assembler program to hit an access error if it tries to load data from the low core (page starting from address zero)?Assembler *PROCESS FLAG(PAGE0) " helps to find cases like MVC TARGET,1But will it be possible to have a run time detection and possibly a dump if the program tries to do things likeLA R5,1MVC TARGET,0(R5)Basically, any way to restrict access of an application program to PSA- first control block? Regards,Syama
