[libvirt] [PATCH 01/23] qemu: driver: Don't call qemuDomainDetermineDiskChain on block jobs

[Peter Krempa]

On Wed, Mar 22, 2017 at 14:21:29 -0500, Eric Blake wrote:
> On 03/15/2017 11:37 AM, Peter Krempa wrote:
> > Our code calls it when starting or re-starting the domain or when
> > hotplugging the disk so there's nothing to be detected.
> > ---
> >  src/qemu/qemu_driver.c | 5 -----
> >  1 file changed, 5 deletions(-)
> > 
> 
> I think I added it here because block jobs have the tendency to rewrite
> the backing chain (think active commit, for example, which reduces the
> backing chain).  Forcing a redetermination is therefore a way to ensure
> no stale data associated with the pre-job chain is left in memory.
> 
> So I'm not sure this is correct.

We re-detect the backing chain when the VM is started, when we reconnect
to it and when we get any of the blockjob-related events.

Additionally if the backing chain is rewritten the code would not be run
since the argument that would rewrite any previously detected data is
false.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20170323/0b1e5328/attachment-0001.sig>