-----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Edward Jaffe Sent: Thursday, November 08, 2007 6:27 PM To: [email protected] Subject: Re: CSA 'above the bar'
Thompson, Steve wrote: > You did say dedicated. And it certainly appears to me to be both > dedicated and reserved (by architectural definition). > > In the MVS world, if a Problem State program attempts to modify > 00000xxx (where x is 0-512 decimal and regardless of the content of > the current base register) and LAP is on... So it is not truly > available (except to the SCP). Otherwise, as I recall [MVS > environments], that page is Key0 non-fetch protected. > > [The above is only for non-Z architected machines. I honestly haven't > read the requisite chapters in the new PoOP.] > We were talking about a *reserved* virtual address range (aka a "hole" or "dead" zone) i.e., one or more pages that are guaranteed to receive a translation exception because the virtual address(es) will never be allocated by the operating system. Page zero does not fit that requirement no matter how hard you squeeze! <snip> My bad. I missed the hole argument (double entendre intended). It's what I get for skipping through the threads. I see the door over here so I'll just show myself out. Regards, Steve Thompson -- All opinions expressed by me are my own and may not necessarily reflect those of my employer. -- ---------------------------------------------------------------------- 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
