It looks like that this series breaks disk unplug
(hw/ide/piix.c:pci_piix3_xen_ide_unplug).
I bisected it and the problem is caused by:
commit 5e95494380ecf83c97d28f72134ab45e0cace8f9
Author: Igor Mammedov <address@hidden>
Date: Wed Feb 5 16:36:52 2014 +0100
hw/pci: switch to a generic hotplug handling for PCIDevice
make qdev_unplug()/device_set_realized() to call hotplug handler's
plug/unplug methods if available and remove not needed anymore
hot(un)plug handling from PCIDevice.
In case if hotplug handler is not available, revert to the legacy
hotplug method for compatibility with not yet converted buses.
Signed-off-by: Igor Mammedov <address@hidden>
Reviewed-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Michael S. Tsirkin <address@hidden>