Currently we do not support in cache=wb so it's not urgent. We'll keep it open mainly for tracking
Kevin's patches to introduce bdrv_(p)write_sync should take care of this.
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: Following writing metadata to a QCOW2 disk image, metadata was not flushed, which could have potentially caused the disk image to become corrupted in the event of system disruption (such as a power outage). With this update, metadata is flushed after being written, thus increasing QCOW2 image integrity, and decreasing the likelihood of image corruption.
verify this bug with kvm-83-207.el5 as https://bugzilla.redhat.com/show_bug.cgi?id=537646#c13, no crash and no error when checking disk image after host power off. Change status to verified.
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/RHSA-2011-0028.html