Revision f0aa7a8b
| ID | f0aa7a8b2d518c54430e4382309281b93e51981a |
loadvm: improve tests before bdrv_snapshot_goto()
This patch improves the resilience of the load_vmstate() function, doing
further and better ordered tests.
In load_vmstate(), if there is any error on bdrv_snapshot_goto(), except if the
error is on VM state device, load_vmstate() will return zero and the VM will be
started with major corruption chances.
The current process:
- test if there is any writable device without snapshot support
- if exists return error get the device that saves the VM state, possible return error but unlikely flush I/O
because it was tested earlier
- run bdrv_snapshot_goto() on devices
- if fails, give an warning and goes to the next (not good!)
- if fails on the VM state device, return zero (not good!)
- check if the requested snapshot exists on the device that saves the VM state
and the state is not zero
- if fails return error open the file with the VM state
- if fails return error load the VM state
- if fails return error return zero
New behavior:
- get the device that saves the VM state
- if fails return error check if the requested snapshot exists on the device that saves the VM state
and the state is not zero
- if fails return error test if there is any writable device without snapshot support
- if exists return error test if the devices with snapshot support have the requested snapshot
- if anyone fails, return error flush I/O
- run snapshot_goto() on devices
- if anyone fails, return error open the file with the VM state
- if fails return error load the VM state
- if fails return error return zero
do_loadvm must not call vm_start if any error has occurred in load_vmstate.
Signed-off-by: Miguel Di Ciurcio Filho <miguel.filho@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Files
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- deleted