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Description of problem: From upstream list... when trying to start / stop a domain with macvtap device (direct type of interface) having a device description like this one here <interface type='direct'> <source dev='static' mode='vepa'/> </interface> then I see netlink related errors if there is a 'virsh edit' session that is happening at the same time. http://www.redhat.com/archives/libvir-list/2011-February/msg00466.html This problem is caused by two bugs in the libnl library, a logic bug, and a (possibly) thread safety bug Version-Release number of selected component (if applicable): 0.8.7-6.el6 How reproducible: Sometimes Steps to Reproduce: 1.virsh edit <macvtap domain> -> do not terminate the edit sessions 2. virsh start <macvtap domain> -> works 3. virsh destroy <macvtap domain> -> leaves a macvtap device due to nl_connect failing 4. virsh start <macvtap domain> -> does not start anymore Actual results: Expected results: Additional info:
Note that Bug 677724 includes a patch to libnl, and also a comment stating that a libnl built with that patch solves the problem.
Since RHEL 6.1 External Beta has begun, and this bug remains unresolved, it has been rejected as it is not proposed as exception or blocker. Red Hat invites you to ask your support representative to propose this request, if appropriate and relevant, in the next release of Red Hat Enterprise Linux.
This BZ is TestOnly, and should have been marked exception, as the fix for 677724 is ON_QA, so this BZ is ready to test as well.
Tested with libvirt-0.8.7-16.el6.x86_64, the guest can be normally started with VEPA. Move to VERIFIED. # virsh edit foo <interface type='direct'> <mac address='52:54:00:00:71:13'/> <source dev='macvtap0' mode='vepa'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> # virsh start foo Domain foo started # virsh destroy foo Domain foo destroyed # virsh start foo Domain foo started
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: The port allocation/de-allocation of the libnl library, which is used by libvirt for macvtap (eg vepa and vnlink) interfaces, was not threadsafe and the logic was incorrect, which resulted in a failure to initialize libnl, and the subsequent failure of the associated libvirt functionality. In particular, the first guest vepa interface started on a host would work, but all subsequent vepa interfaces would fail. Port allocation/de-allocation and logic is now fixed in libnl, and the failures in libvirt no longer occur.
Technical note updated. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. Diffed Contents: @@ -1 +1 @@ -The port allocation/de-allocation of the libnl library, which is used by libvirt for macvtap (eg vepa and vnlink) interfaces, was not threadsafe and the logic was incorrect, which resulted in a failure to initialize libnl, and the subsequent failure of the associated libvirt functionality. In particular, the first guest vepa interface started on a host would work, but all subsequent vepa interfaces would fail. Port allocation/de-allocation and logic is now fixed in libnl, and the failures in libvirt no longer occur.+The port allocation/de-allocation of the libnl library, which is used by libvirt for macvtap (for example, vepa and vnlink) interfaces, was not threadsafe and the logic was incorrect. This resulted in a failure to initialize libnl, and a subsequent failure of the associated libvirt functionality. In particular, the first guest vepa interface started on a host would work, but all subsequent vepa interfaces would fail. Port allocation/de-allocation and logic is now fixed in libnl, and the failures in libvirt no longer occur.
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-2011-0596.html