This is caused by a bug in supermin:
https://github.com/libguestfs/supermin/commit/158854e3ba4be7f6b8d81f662dd...
It was fixed 6 months ago, so Ubuntu needs to upgrade supermin
to include the fix.
By the way this has been reported several times in the past week. I
guess that Ubuntu have just released a new kernel or something.
Rich.
--
Richard Jones, Virtualization Group, Red Hat
http://people.redhat.com/~rjones
Read my programming and virtualization blog:
http://rwmj.wordpress.com
libguestfs lets you edit virtual machines. Supports shell scripting,
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