Comment 6 for bug 1352875

We're experiencing this with the 32MB cirrus inane, as well as larger images like 1GB.

The backend devices are FC and iSCSI attached block devices; this is easily reproduced with and without multipath.

The current code does with for the convert to complete, but the writes are not synced to the device and the buffers are not flushed before detaching the volume.
and I assume (didn't strace to verify) that the qemu binary does not open the block device with O_DIRECT