See here:
$ ./qemu-img create -f qcow2 backing.qcow2 64M
Formatting 'backing.qcow2', fmt=qcow2 size=67108864 encryption=off
cluster_size=65536 lazy_refcounts=off refcount_bits=16
$ ./qemu-img create -f qcow2 -b backing.qcow2 ./top:image.qcow2
qemu-img: ./top:image.qcow2: Could not open './top:backing.qcow2':
No such file or directory
:-(
(See also: https://bugzilla.redhat.com/show_bug.cgi?id=1212715)
Max Reitz (2):
block: Fix backing paths for filenames with colons
iotests: Add test for colon handling
block.c | 15 ++++++---
tests/qemu-iotests/126 | 76 ++++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/126.out | 16 ++++++++++
tests/qemu-iotests/group | 1 +
4 files changed, 103 insertions(+), 5 deletions(-)
create mode 100755 tests/qemu-iotests/126
create mode 100644 tests/qemu-iotests/126.out
--
2.9.4