Red Hat Bugzilla – Bug 250766
kernel panic in 32-bit domU when running on x86_64 dom0
Last modified: 2008-05-21 10:48:26 EDT
Description of problem: I originally created a paravirutalized guest, which is stored on a logical volume, on a 32-bit RHEL 5.0 dom0 installation. I then moved this logical volume , using nc, to a new test host which is running RHEL 5.1 Beta x86_64. I copied over the xen config file as well. Now, when I try to start the guest, I see pygrub start, the kernel boot, and then a kernel panic occurs in the domU right when trying to mount root. The md5sum of the logical volume where the domU is installed checks out against the original md5sum from the 32-bit box. Version-Release number of selected component (if applicable): # rpm -qa | grep xen kernel-xen-2.6.18-36.el5 xen-libs-3.0.3-33.el5 xen-3.0.3-33.el5 xen-libs-3.0.3-33.el5 How reproducible: Always Steps to Reproduce: 1) Copy over the logical volume containing the 32-bit domU installation along with the config file from /etc/xen. 2) Try to start the 32-bit domU, you will see pygrub start, the kernel boot, and then panic right in the domU before trying to mount the root fs. Actual results: A kernel panic occurs in the domU. Expected results: The system boots completely. Additional info: stack trace from kernel panic attached. I tried to capture a vmcore by enabling dumping in /etc/xen/xend-config.sxp, however, only 0 sized vmcores are generated. -rw------- 1 root root 0 Aug 3 10:43 2007-0803-1043.26-rhel5Client.13.core-incomplete
Created attachment 160615 [details] stack trace from the domU kernel panic.
Paul, 32-on-64 support is much improved with 5.2. Can you give it a whirl and let us know if it works better? Save/restore/live migrate is still known to fail for 32-on-64, but most other things should work. Thanks, Chris Lalancette
Hi Chris, Running my 32-bit domU on a 64-bit dom0 with kernel 2.6.18-79.el5xen if fine. I'm a happy camper. Thanks, Paul
This was fixed by the rebase of the Xen Hypervisor to 3,1.2 (bz 318891). Setting flags to process for RHEL 5.2.
verifying, I've been running a 32-bit domU on a 64-bit dom0 for a couple of months now without issues.
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 the 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-2008-0314.html