action #38822
Qemu: Could not open backing file: Cannot reference an existing block device with additional options or a new filename
Start date:
2018-07-25
Due date:
% Done:
0%
Estimated time:
Difficulty:
Description
When trying to revert to a snapshot QEMU dies with the following error or something similar:
-blockdev driver=qcow2,node-name=hd0-overlay1,file=hd0-overlay1-file,cache.no-flush=on,backing=hd0: Could not open backing file: Cannot reference an existing block device with additional options or a new filename
The backing file is the hd0 block device which is specified on the command line. Possibly we should not specify block devices used as backing files on the command line and just allow them to be read from the overlay file. It is not clear what the expected usage is.
Related issues
History
#1
Updated by rpalethorpe almost 5 years ago
Updated by - Copied from action #38813: Qemu backend rewrite fallout added
#2
Updated by rpalethorpe almost 5 years ago
Looking at qemu/block.c I suspect we can only specify options (e.g. cache.no-flush=on) on one of the blockdevices in the chain.
#4
Updated by rpalethorpe almost 5 years ago
- Status changed from New to Feedback
- Assignee set to rpalethorpe
#5
Updated by rpalethorpe almost 5 years ago
- Status changed from Feedback to Resolved
#6
Updated by szarate almost 5 years ago
Updated by - Target version changed from Current Sprint to Done