I don't entirely agree. The action of the guest did not cause harm to CP, it was the action of the operations staff which did. This is not a denial of service case that I can see.
Bill Holder z/VM Development, Memory Management team leader, IBM On Tue, 15 Sep 2009 09:59:09 -0700, Schuh, Richard <rsc...@visa.com> wrot e: >Maybe CP couldn't know that the guest would do something bad, but it sho uld know that it has opened itself to the possibility that the guest could, i n normal operation, cause the problem. >One of Alan's first precepts of information security and integrity is th at the guest cannot be allowed to harm the CP. This clearly violates that. > >Regards, >Richard Schuh > > > >> -----Original Message----- >> From: The IBM z/VM Operating System >> [mailto:ib...@listserv.uark.edu] On Behalf Of Tom Duerbusch >> Sent: Tuesday, September 15, 2009 9:19 AM >> To: IBMVM@LISTSERV.UARK.EDU >> Subject: Re: VM lockup due to storage typo >> >> CP wouldn't know at IPL time, the guest would, not could, but >> would cause such harm. >> >> Just because you say you can use xxx GB, doesn't mean you >> would actually use them. >> >> When page fills, it over flows to spool. >> When spool fills, CP abends on the next pageout. >> >> Tom Duerbusch >> THD Consulting >> >> >>> Marcy Cortes <marcy.d.cor...@wellsfargo.com> 9/15/2009 >> 11:02 AM >>> >> See a thread on this list with subject "Sanity check?" from >> Oct 2007 for what happened when I did the same thing ;) >> >> You probably filled page space. >> >> I still think IBM should refuse to IPL a guest that will >> cause such harm. >> >> >> Marcy >> >> "This message may contain confidential and/or privileged >> information. If you are not the addressee or authorized to >> receive this for the addressee, you must not use, copy, >> disclose, or take any action based on this message or any >> information herein. If you have received this message in >> error, please advise the sender immediately by reply e-mail >> and delete this message. Thank you for your cooperation." >> >> >> -----Original Message----- >> From: The IBM z/VM Operating System >> [mailto:ib...@listserv.uark.edu] On Behalf Of Lee Stewart >> Sent: Tuesday, September 15, 2009 8:39 AM >> To: IBMVM@LISTSERV.UARK.EDU >> Subject: [IBMVM] VM lockup due to storage typo >> >> Does anyone have an idea of how we might have gotten out of >> this without an IPL? >> >> VM LPAR has 175G of memory and a flock of Linux Oracle guests... >> Several guests needed more memory added so the directory was >> updated and one by one the guests shutdown, logged off and >> back on. So far, so good. >> >> But... In changing the memory for many guests, and it being >> late at night after a long day, while meaning to set a >> guest's memory to 9728M, it got set to 9728G. When that >> guest was cycled we see the message on the console that it's >> memory was limited to 8TB (HCPLGN093E), then the VM system >> appeared to freeze. >> >> We couldn't get in via TCP/IP, or the HMC Operating System >> Messages screen, or the HMC Integrated 3270. >> >> Finally had to IPL. Even that was wierd as I'd have >> expected the Load >> Normal to shutdown, it just IPLed. We did NoAutolog, fixed the typo >> and all came back up ok... >> >> I suspect CP was scrambling paging everything in the world >> out as Linux >> tried to initialize that 8TB of memory... But I'm surprised >> I couldn't >> even get into the HMC consoles (to kill just that one guest >> as opposed to all of them).. >> >> Any thoughts? >> Lee >> -- >> >> Lee Stewart, Senior SE >> Sirius Computer Solutions >> Phone: (303) 996-7122 >> Email: lee.stew...@siriuscom.com >> Web: www.siriuscom.com >> ======================== ========================= =======================
