guestmount --ro fails in fedora 27 on running VM?
I've just gotten everything switched to fedora 27,
and I'm now finding that guestmount fails on a
running VMs disk image. I used to be able to
mount --ro and see a read only snapshot of the
disk even if the KVM was still running. Now I
get a lot of errors when I run:
LIBGUESTFS_DEBUG=1 LIBGUESTFS_TRACE=1 guestmount -d centinil -i --ro mnt
One of the errors that appears is:
qemu-img: /tmp/libguestfssn6HDK/overlay1.qcow2: Failed to get shared "write"
lock
Is another process using the image?
And, yes, another process is using the image, but --ro
used to work even when that was the case.
Should I submit a bug on this, or is this change
deliberate?
(The guestmount does seem to work fine once the VM is
shut down).