Re: [libvirt] [PATCH] qemu: hotplug: fail when net device detach times out

On Tue, Mar 13, 2018 at 02:07:08PM +0000, Jonathan Davies wrote: > qemuDomainDetachNetDevice should not treat a timeout in a call to > qemuDomainWaitForDeviceRemoval as success. Instead, it should treat it > as failure -- this is the intention behind having a timeout. Actually this is intentional current behaviour. See the API docs for virDomainDetachDeviceFlags: * Beware that depending on the hypervisor and device type, detaching a device * from a running domain may be asynchronous. That is, calling * virDomainDetachDeviceFlags may just request device removal while the device * is actually removed later (in cooperation with a guest OS). Previously, * this fact was ignored and the device could have been removed from domain * configuration before it was actually removed by the hypervisor causing * various failures on subsequent operations. To check whether the device was * successfully removed, either recheck domain configuration using * virDomainGetXMLDesc() or add a handler for the VIR_DOMAIN_EVENT_ID_DEVICE_REMOVED * event. In case the device is already gone when virDomainDetachDeviceFlags * returns, the event is delivered before this API call ends. To help existing * clients work better in most cases, this API will try to transform an * asynchronous device removal that finishes shortly after the request into * a synchronous removal. In other words, this API may wait a bit for the * removal to complete in case it was not synchronous.