To add to Jim's point. This is from a z/OS 2.5 manual. ASLR(NO|YES|YES3164|YES64) Indicates whether address spaces on this system are subject to address space layout randomization (ASLR). For information about the implications of enabling ASLR and how to exclude individual jobs from ASLR, see Address space layout randomization in z/OS MVS Initialization and Tuning Guide. The ASLR values are: NO Indicates that the 24-bit and 31-bit low private area and the 64-bit private area of address spaces are not subject to address space layout randomization. YES Indicates that the 24-bit and 31-bit low private area and the 64-bit private area of address spaces are subject to address space layout randomization. YES3164 Indicates that only the 31-bit low private area and the 64-bit private area of address spaces are subject to address space layout randomization. YES64 Indicates that only the 64-bit private area of address spaces is subject to address space layout randomization. Default: NO
Also Mark I have to ask. Are all these systems setup the same way? That is things like CSA, SQA, LPA and other stuff? I've seen small differences in systems because of things like maintenance level or software stack. Naturally there is the whole rounding thing that happens that can affect where the private area starts. Paul -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Jim Mulder Sent: Monday, September 9, 2024 7:20 PM To: [email protected] Subject: Re: 24-bit private region on z16 processor I would expect that if Address Space Layout Randomization is active. Is ASLR(YES) specified in DIAGxx? The D DIAG command, or VERBX IGVDGNIP under IPCS, will tell you. Jim Mulder -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Mark Jacobs Sent: Monday, September 9, 2024 6:16 PM To: [email protected] Subject: Re: 24-bit private region on z16 processor I'm 99% sure those parameters aren't in any of the systems where I'm being weirded out as it relates to where low private begins when I look at it using SDSF VMAP, but I'll check tomorrow. Mark Jacobs Sent from ProtonMail, Swiss-based encrypted email. GPG Public Key - https://api.protonmail.ch/pks/lookup?op=get&[email protected] On Monday, September 9th, 2024 at 4:40 PM, Allan Staller <[email protected]> wrote: > Classification: Confidential > > "Low Core" generally extend up to about x'6000' (give or take). This is the > start of low private. > V=R and ADDRSPC storage IIRC is just above this so actual "low private" may > start (e.g. x'8000') depending on values for V=R and ADDRSPC=REAL stoarge. > > FWIW, these 2 parameters date from "day 1" of virtual storage and are > probably useless in this day and age. > If they are still present in IEASYSxx, I would suggest removing them when > convenient. > > HTH, > > -----Original Message----- > From: IBM Mainframe Discussion List [email protected] On Behalf > Of Mark Jacobs > > Sent: Monday, September 9, 2024 3:05 PM > To: [email protected] > Subject: Re: 24-bit private region on z16 processor > > [CAUTION: This Email is from outside the Organization. Unless you > trust the sender, Don’t click links or open attachments as it may be a > Phishing email, which can steal your Information and compromise your > Computer.] > > I'm not talking about the top of the 24-bit private region, I'm looking at > the beginning/bottom of the region and it's starting all over the place. > > Mark Jacobs > > Sent from ProtonMail, Swiss-based encrypted email. > > GPG Public Key - > https://api.protonmail.ch/pks/lookup?op=get&search=markjacobs@protonma > il.com > > > > > On Monday, September 9th, 2024 at 2:30 PM, Mike Schwab > [email protected] wrote: > > > Varies by operating system level occasionally PTF, and user > > configuration such as TSO in (non-)LPA area. > > > > On Mon, Sep 9, 2024 at 8:25 AM Mark Jacobs > > [email protected] wrote: > > > > > Silly question. Is there anything different as it relates to sizing of > > > the 24-bit private region on z16 processors? > > > > > > Mark Jacobs ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
