[PATCH] Re: [libvirt] Silently ignored virDomainRestore failures

[Charles Duffy]

Charles Duffy wrote:
>     For existing QEMU, it might be sufficient to just put an arbitrary
>     'sleep(5)' before issuing 'cont', which would at least give it a
>     reasonable chance of avoiding the race condition.
> 
> Well -- I wasn't going to submit the patch I'm now using internally 
> (using and waiting for a sigil on stderr when migrate_url is "stdin"), 
> but I suppose that with an else clause doing a sleep it might actually 
> be the closest available option to a Right Thing for preexisting qemu.
> 
> I'll wait to hear back today from the contractors testing with it (they 
> were hitting this race condition frequently) and post an amended copy 
> here if it gets their thumbs-up.

Attached is what I'm presently using as a workaround until I have a 
proper ("info incoming") approach implemented. It is perhaps excessively 
paranoid (the extra .5sec of delay on the stdin case may not be needed), 
but we haven't been able to reproduce the issue with it applied.
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