Description of problem: After upgrading to the latest mcelog package on RHN, my Xen domU RHEL 5 guest is spitting out an mcelog error email every hour: /etc/cron.hourly/mcelog.cron: mcelog: Cannot mmap 0xf0000: Bad address Version-Release number of selected component (if applicable): mcelog-0.9pre-1.26.el5 Steps to Reproduce: 1. yum upgrade (to 5.4 beta) 2. wait for error emails to come in 3. Expected results: mcelog should not get any useful info on a Xen PV guest, but it should not spit out an error message either. Additional info: # uname -a Linux shelob.surriel.com 2.6.18-128.1.10.el5xen #1 SMP Wed Apr 29 14:24:51 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux I believe we should fix this bug because removing the printf is very low risk, we can save our users some annoyance and we can avoid the support calls that would be coming in about this.
<riel> prarit: probably easiest from the shell script that's invoked by cron * dkl (~dkl.redhat.com) has joined #devel <prarit> riel: yup. Is there something I can look for in /proc or /sys to identify a PV domU? <riel> (1) /proc/xen exists and (2) the contents of /sys/hypervisor/uuid are not all zeroes (dom0 has all zeroes there) <riel> for some reason I do not know, /proc/xen/privcmd now shows up in domU too :) <prarit> riel: Thanks :) .... looking at a freshly installed domU now.
Created attachment 354485 [details] RHEL5 mcelog.cron fix
Created attachment 354487 [details] RHEL5 new spec file
Bare-metal, domU, and dom0 tests all successful with the above fix. P.
Release note added. If any revisions are required, please set the "requires_release_notes" flag to "?" and edit the "Release Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: mcelog is unable to obtain MCE data from paravirtualized Xen guests on a system. Previously, each time that mcelog tried and failed to obtain this data, it would generate an error report -- by default, once per hour. These error reports could mislead users to think that there was a problem with their system. Now, mcelog does not generate error reports when it cannot obtain MCE data from paravirtualized Xen guests, and therefore avoids any potential confusion.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2009-1374.html