Public bug reported: While doing 'qemu-img rebase' for linking to a different backing file, if the old backing file does not exist, the command fails. During this failure, the error message shown is misleading. e.g. qemu-img rebase -b <backing_file> <filename> throws error saying "Could not open <filename>" Ideally it should "Could not open <old_backing_file>"
snippet - [root@oxy-dev ~]# qemu-img info /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk image: /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk file format: qcow2 virtual size: 20G (21474836480 bytes) disk size: 174M cluster_size: 65536 backing file: /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b Format specific information: compat: 1.1 lazy refcounts: false [root@oxy-dev ~]# mv /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a [root@oxy-dev ~]# file !$ file /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a: x86 boot sector; partition 1: ID=0x83, active, starthead 32, startsector 2048, 409600 sectors; partition 2: ID=0x8e, starthead 159, startsector 411648, 16365568 sectors, code offset 0xc0 [root@oxy-dev ~]# file /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b: cannot open (No such file or directory) [root@oxy-dev ~]# qemu-img rebase -b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk qemu-img: Could not open '/opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk': Could not open file: No such file or directory [root@oxy-dev ~]# qemu-img version 1.5.3 OS: RHEL7 - 3.10.0-229 libvirtd (libvirt) 1.2.8 ** Affects: qemu Importance: Undecided Status: New -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1524546 Title: qemu-img rebase error message mentions wrong file name Status in QEMU: New Bug description: While doing 'qemu-img rebase' for linking to a different backing file, if the old backing file does not exist, the command fails. During this failure, the error message shown is misleading. e.g. qemu-img rebase -b <backing_file> <filename> throws error saying "Could not open <filename>" Ideally it should "Could not open <old_backing_file>" snippet - [root@oxy-dev ~]# qemu-img info /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk image: /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk file format: qcow2 virtual size: 20G (21474836480 bytes) disk size: 174M cluster_size: 65536 backing file: /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b Format specific information: compat: 1.1 lazy refcounts: false [root@oxy-dev ~]# mv /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a [root@oxy-dev ~]# file !$ file /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a: x86 boot sector; partition 1: ID=0x83, active, starthead 32, startsector 2048, 409600 sectors; partition 2: ID=0x8e, starthead 159, startsector 411648, 16365568 sectors, code offset 0xc0 [root@oxy-dev ~]# file /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383b: cannot open (No such file or directory) [root@oxy-dev ~]# qemu-img rebase -b /tmp/3559241a79b79ae663ec6e3d9b75d469967b383a /opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk qemu-img: Could not open '/opt/stack/data/nova/instances/94864a64-ebf8-45e6-a777-615921216a0a/disk': Could not open file: No such file or directory [root@oxy-dev ~]# qemu-img version 1.5.3 OS: RHEL7 - 3.10.0-229 libvirtd (libvirt) 1.2.8 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1524546/+subscriptions