Red Hat Bugzilla – Bug 251288
booting a rhel3u9 HVM guest with "apic = 0" in the guest config file causes kernel panic on guest.
Last modified: 2013-11-03 20:33:59 EST
Description of problem:
This is rather interesting. When booting a rhel3u9 hvm UP guest with apic = 0
in the guest config file, guest kernel panics with the attached backtrace. Yet
booting the same guest with "noapic" passed to the kernel line in grub works fine.
Version-Release number of selected component (if applicable):
# rpm -q libvirt xen kernel-xen
Steps to Reproduce:
1. Install a rhel3u9 HVM guest.
2. Edit the config file to change apic = 0 to apic = 1
3. Start the guest.
Created attachment 160884 [details]
guest kernel backtrace
Please confirm this behavior on the most current beta tree.
(In reply to comment #2)
> Please confirm this behavior on the most current beta tree.
This behavior is confirmed with the RHEL5.1-Server-20070809.5 tree.
# rpm -q xen kernel-xen libvirt
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release. Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products. This request is not yet committed for inclusion in an Update
This request was previously evaluated by Red Hat Product Management
for inclusion in the current Red Hat Enterprise Linux release, but
Red Hat was unable to resolve it in time. This request will be
reviewed for a future Red Hat Enterprise Linux release.
the RHEL5.2 release notes will be dropped to translation on April 15, 2008, at
which point no further additions or revisions will be entertained.
a mockup of the RHEL5.2 release notes can be viewed at the following link:
please use the aforementioned link to verify if your bugzilla is already in the
release notes (if it needs to be). each item in the release notes contains a
link to its original bug; as such, you can search through the release notes by
(In reply to comment #7)
> the RHEL5.2 release notes will be dropped to translation on April 15, 2008, at
> which point no further additions or revisions will be entertained.
> a mockup of the RHEL5.2 release notes can be viewed at the following link:
> please use the aforementioned link to verify if your bugzilla is already in the
> release notes (if it needs to be). each item in the release notes contains a
> link to its original bug; as such, you can search through the release notes by
> bug number.
I did testing on kernel-xen-2.6.18-191.el5 and xen-3.0.3-105.el5 and the result is the same like stated in comment #0, i.e. the RHEL 3u9 x86_64 is causing the kernel panic with the apic disabled ("apic = 0" ) but i386 version is working fine without APIC. Apparently APIC support is required for x86_64 to work.
Paolo, I am not having RHEL 4 kernel sources downloaded but I know you have, could you please have a look whether there is something to prevent x86_64 version to boot without APIC enabled?
x86_64 machines all have an APIC and the kernel requires it for proper operation.
(i.e. it can be disabled with noapic, but if noapic is not given, the kernel won't check whether it's present or not).
(In reply to comment #11)
> (i.e. it can be disabled with noapic, but if noapic is not given, the kernel
> won't check whether it's present or not).
Ok, great, that way I am closing this one as NOTABUG.
Thanks for your input Paolo,
This bug was closed during 5.5 development and it's being removed from the internal tracking bugs (which are now for 5.6).