Red Hat Bugzilla – Bug 233375
Make SOS flag the situation when running on a fully virtualized guest, but with a -xen kernel
Last modified: 2013-04-12 15:05:36 EDT
Description of problem:
Fully virtualized RHEL5 guests are usually run using the normal, bare-metal
kernel (i.e. kernel-2.6.18-8.el5.i686.rpm). However, it is possible to install
the paravirtualized Xen kernel (kernel-xen-2.6.18-8.el5.i686.rpm) inside the
fully virtualized domain, and have it boot. While this technically works, it is
not well tested, not entirely stable, and not supported. The xen plugin for
sosreport should identify this situation and flag it in the generated report.
Steve, I can actually do this work, although I might need a little bit of
guidance from you.
In my opinion sosreport should only worry about gathering the information. This
check should be performed later when analysing sosreport's results.
What might be interesting is introduce this tool as part of the sosreport
project, which takes a sosreport result's tree and parses it in a similar way as
checksysreport does. I will speak with Pierre (checksysreport developer) if he
has already done some work in this direction.
OK, great. Thanks for taking a look.
Created attachment 152714 [details]
A quick patch to the "xen.py" module to check if running a -xen kernel on HVM guest
After talking with Steve Conklin, we decided this would be an easy thing to do,
and we can do it in sosreport. We might ALSO want to do it in checksysreport.
In any case, the attached patch applies on top of the current upstream SOS xen
plugin, and flags the situation when running a -xen (paravirtualized) kernel
INSIDE a fully virtualized guest. This is known to cause problems. Note that
the patch is currently untested; I'll test it out later today or tomorrow.
Created attachment 152818 [details]
An updated patch for the xen plugin that reports a PV kernel on HVM
I've tested this updated patch on an HVM guest both with a normal kernel
(i.e. 2.6.18-8.el5) and with a "wrong" xen kernel (i.e. 2.6.18-8.el5xen). It
seems to do the right thing in both cases. The only difference between this
patch and the previous one is that it adds a newline to the ends of the lines.
I think this is now ready to be committed to SVN.
The patch looks good. Agreed with Navid that sosreport should only worry about
gathering information, but a warning for FV guest running a -xen kernel is useful.
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.