Comment 4 for bug 1491216

Reviewed: https://review.openstack.org/237547
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=92ae0f1077e4c5916d99777b032aaf0840e7ab93
Submitter: Jenkins
Branch: master

commit 92ae0f1077e4c5916d99777b032aaf0840e7ab93
Author: Chung Chih, Hung <email address hidden>
Date: Tue Oct 20 12:41:46 2015 +0000

    libvirt - Add log if libguestfs can't read host kernel

    Host's kernel only allows a root user to have read/write permission in
    ubuntu. If compute-service didn't have read permission then libguestfs
    will launch image fail.

    In libguestfs offical FAQ site had point out this issue, following is
    the link
    http://libguestfs.org/guestfs-faq.1.html#binaries
    It had suggested users to change host's kernel permission. But this
    action should be handled by other patch. Here only give a hint what's
    going wrong.

    Change-Id: I36c93610831e2935d46f7ee37f95619fe6dc1481
    Related-Bug: 1413142
    Closes-Bug: 1491216