Bug 810222
| Summary: | Revert "[virt] xen: mask MTRR feature from guest BZ#750758" | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Andrew Jones <drjones> |
| Component: | kernel | Assignee: | Andrew Jones <drjones> |
| Status: | CLOSED ERRATA | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | urgent | Docs Contact: | |
| Priority: | urgent | ||
| Version: | 6.2 | CC: | kzhang, leiwang, moli, qguan, qwan, xen-maint |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | xen | ||
| Fixed In Version: | kernel-2.6.32-262.el6 | Doc Type: | Bug Fix |
| Doc Text: |
No documentation needed.
|
Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | 2012-06-20 08:45:29 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 653816 | ||
Patch(es) available on kernel-2.6.32-262.el6 Verified with kernel-2.6.32-269.el6. With this build, kdump service can start successfully and works well in xen HVM guest. The latest build contains the following fixes: Bug 810222 - Revert "[virt] xen: mask MTRR feature from guest BZ#750758" (fix in -262) Bug 811815 - [FJ6.2 Bug]: kdump service fails with the message "Kdump is unsupported on this kernel" (fix in -266) Bug 815785 - kdump fails with lapic error in xen hvm guest (fix in -269). With all of the above three fixes integrated, kdump in RHEL6.3 xen hvm guest works well now. So verify these 3 bugs together. Test steps: [1] Add the kernel command line parameter xen_emul_unplug=never to the kernel's command line and boot. [2] Start the kdump service. [3] Blacklist the drivers used for xen emulated device by adding the following tree lines to /etc/modprobe.d/blacklist.conf: blacklist ata_piix blacklist 8139too blacklist 8139cp [4] Remove the xen_emul_unplug=never kernel command line parameter added in step 1 and add the kernel command line xen_emul_unplug=unnecessary, then reboot. [5] Ensure that the kdump service has started. [6] Run echo c >/proc/sysrq-trigger to force a crash that should invoke kdump
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New Contents:
No documentation needed.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHSA-2012-0862.html |
In order to support kdump for xen hvm guests we need to revert commit c16ccd2dba7492cee6cfe4b80f4c49746fe85c96 Author: Igor Mammedov <imammedo> Date: Thu Dec 1 17:11:00 2011 -0500 [virt] xen: mask MTRR feature from guest BZ#750758 It's still not clear why this patch impacts kdump, but as it's a lower priority patch to the support of kdump we'll revert it now and figure out how to bring it back during 6.4 development. In essence we're deferring bug 750758 to 6.4, even though it's already been done. This bug will be used for the 6.3 reversion patch. Bug 810221 will be used to bring it back for 6.4.