[DRBD-user] [PATCH] xen-blkback: Switch to closed state after releasing the backing device

[Roger Pau Monné]

On Fri, Sep 07, 2018 at 09:23:19AM +0200, Valentin Vidic wrote:
> On Fri, Sep 07, 2018 at 09:15:30AM +0200, Roger Pau Monné wrote:
> > I'm not sure that's a good idea, there are a lot of backends (apart
> > from blkback), and the tools won't know whether a specific backend
> > supports such state or not. Also the current protocol and states are
> > shared between all the Xen PV devices, so new additions should be
> > considered very carefully.
> 
> Sure, I understand.
> 
> > IMO the best options are either calling vbd_free/vbd_create at proper
> > stages in blkback or changing the hotplug script so it waits for the
> > device to have no open clients.
> 
> Changing the block-drbd script would be ideal for me too, but I don't
> think that piece of DRBD state is exposed at the moment.

Then I'm afraid you will have to look into the vbd_free/create fix.

Thanks, Roger.