On 06/19/2014 10:49 AM, Eric Blake wrote:
> if qemu allows shared BDS, and I am able to open 'base' as a shared BDS
> for both disks, then an attempt to block-commit img1 into base will be
> blocked because base is still in use by img2.  But as a management app,
> I shouldn't be attempting that in the first place.  Yes, it would be
> nice if qemu blocks me from being stupid; but even if qemu allows shared
> BDS, if I don't open a shared BDS on 'base' in the first place, it is no
> different than if qemu doesn't allow shared BDS.  Either way, it's not
> qemu's fault if I, as management, try to commit into a file that is in
> use by more than one chain.
> 

That's what I meant to say,

> 
> if I am not able to do a shared BDS, I'm still
> and as the management, I did not request that qemu open 'base' as a
> shared BDS between both

and this was leftover ramblings that I was experimenting with, but
forgot to delete once I had the paragraph above the way I liked it.
Sorry for any confusion.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org