> -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On > Behalf Of Peter Relson > Sent: Friday, January 26, 2007 5:36 AM > To: [email protected] > Subject: Re: Cross Memory and AR ASC Mode > /snip/ > > Jeffrey Smith mentioned LASP: I hope it isn't surprising to anyone that > you > are not supposed to use that instruction, just as you are not supposed to > do all sorts of things provided for the base OS to use in order to make it > possible for your applications to run (including such obvious things as > using LCTL to set various things). > /snip/ > > Peter Relson
Just to be clear, I mentioned LASP as one of the many instructions intended for the operating system to use for preparing a unit of work for dispatch. When a unit of work is suspended, its current primary and secondary ASN are saved somewhere and later restored with LASP (or equivalent). A similar function may occur when popping a PC state entry with the Program Return (PR) instruction. Either way, before the advent of ASN-LX-REUSE-FACILITY, (ALRF), there was no way to know for sure whether the ASN was the same "logical" address space that was bound to the unit of work at suspension. Setting secondary addressability (SSAR) to an arbitrary space clearly violates system integrity rules. On a sandbox system intended to crash and burn, who cares? On a production system, it's clearly a no-no, but I would guess there are still some ISV products being used on production systems, which violate system integrity rules in a variety of ways, including inappropriately referencing arbitrary address spaces, elevating authorization for a unit of work running in an insecure environment, using problem key storage in the common area, the list goes on and on. I've seen all kinds of such shenanigans and I was slapped down by management when I complained. (But I'm not bitter about it....eek!) Two cents worth. Your mileage may vary. Cheers Jeffrey D. Smith Principal Product Architect Farsight Systems Corporation 700 KEN PRATT BLVD. #204-159 LONGMONT, CO 80501-6452 303-774-9381 direct 303-484-6170 FAX http://www.farsight-systems.com/ see my résumé at my website (yes, I am looking for employment) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
