[libvirt] [PATCH] qemuPrepareNVRAM: Save domain after NVRAM path generation

[Michal Privoznik]

On 25.09.2014 19:21, Martin Kletzander wrote:
> On Thu, Sep 25, 2014 at 03:00:06PM +0200, Michal Privoznik wrote:
>> On a domain startup, the variable store path is generated if needed.
>> The path is intended to be generated only once. However, the updated
>> domain definition is not saved into config dir rather than state XML
>
> the 'is not' confused me in here.  Did you mean s/not // by any chance?

Nope.

>
>> only. So later, whenever the domain is destroyed and the daemon is
>> restarted, the generated path is forgotten and the file may be left
>> behind on virDomainUndefine() call.
>>
>
> And if you did really mean "the updated domain definition is saved
> into config dir rather than state XML only", why isn't that done when
> the domain is defined (in PostParse() for example) like address
> assignment, etc.?
>

Well, the main reason is that path I'd like to keep path generation 
close to copying from the template/master var store. And the copying 
doesn't need to be done until the domain is started. But once the path 
is generated it shoul persist in the config XML. However, early in the 
qemuProcessStart() the vm->def and vm->newDef are swapped to create live 
XML. Anything that's done to domain def after the swap is reflected in 
live XML only. That's why the config didn't need to be saved. But now, 
with NVRAM things have changed.

What we can do (post release preferably) is to break qemuPrepareNVRAM() 
into smaller pieces: the NVRAM path would be generated in PostParse() 
callback and the file creation somewhere in qemuProcessStart.

Michal