On Tue, Sep 26, 2017 at 12:05:47PM +0200, Thomas Huth wrote: > On 21.09.2017 19:56, Eduardo Habkost wrote: > > On Thu, Sep 07, 2017 at 11:22:42AM +0200, Thomas Huth wrote: > >> qdev_unplug() bails out with an assertion if the user tries to device_del > >> a hot-plugged device that does not have a hotplug controller. > >> Unfortunately, > >> our devices are all marked with hotpluggable = true by default (see the > >> device_class_init() function in qdev.c), so it currently can happen that > >> the user runs into this situation and QEMU gets terminated unexpectedly: > >> > >> $ qemu-system-aarch64 -M virt -nographic -nodefaults -monitor stdio -S > >> QEMU 2.10.50 monitor - type 'help' for more information > >> (qemu) device_add aux-to-i2c-bridge,id=x > >> (qemu) device_del x > >> ** > >> ERROR:qdev-monitor.c:872:qdev_unplug: assertion failed: (hotplug_ctrl) > >> Aborted (core dumped) > >> > >> Hotplugging devices without a hotplug controller does not make much sense, > >> so we should disallow this during the device_add process already! > >> > >> Suggested-by: Paolo Bonzini <pbonz...@redhat.com> > >> Signed-off-by: Thomas Huth <th...@redhat.com> > > > > I'm queueing this on machine-next. We still want it even if we > > apply the patch that changes TYPE_DEVICE to hotpluggable=false by > > default, right? > > OK, just to be sure: Please de-queue it again. As you already mentioned > in another mail, there are situations where this does not work (e.g. > when one hot-pluggable device wants to instantiate another hot-pluggable > device internally).
I just dequeued it. > > But maybe we could add the test for the availability of a hot-plug > controller to qmp_device_add() instead? (I haven't had a closer look at > that yet, though). I'm unsure about this. Now we know we have some devices that work without a hotplug controller, so what's the reason device_add must always require one? -- Eduardo
