On Thu, Aug 18, 2016 at 10:57:04AM +1000, David Gibson wrote: > On Wed, Aug 17, 2016 at 07:31:38PM +0530, Bharata B Rao wrote: > > sPAPR supports only Core level CPU plug and unplug, but nothing > > prevents user from issuing a device_del on the underlying thread > > device by using its qom path directly. This hits g_assert(hotplug_ctrl) > > in qdev_unplug(). > > > > Gracefully reject such unplug requests from ->unplug() handler > > > > Reported-by: Shivaprasad G Bhat <sb...@linux.vnet.ibm.com> > > Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com> > > Why isn't there a graceful failure if we return NULL from the > hotplug_handler()? Doesn't that indicate a bug in the generic code? > Couldn't the same error be triggered by attempting to unplug some > other random device - say the RTC on x86, or the NVRAM on POWER?
True, realized that this error can be triggered for other devices as well like dr-connector or icp devices. So it definitely doesn't make sense to explicitly return a non-NULL hotplug_handler for all of these and then fail the unplug gracefully from ->unplug() like I am doing here for CPU thread devices. Hence, this particular fix isn't needed right now. May be we can gracefully error out for all such cases from qdev_unplug(). Regards, Bharata.
