On Sun, Nov 14, 2010 at 11:57:52AM +0900, Isaku Yamahata wrote: > On Sat, Nov 13, 2010 at 10:59:15PM +0200, Michael S. Tsirkin wrote: > > On Fri, Nov 12, 2010 at 09:50:30PM +0900, Isaku Yamahata wrote: > > > On Fri, Nov 12, 2010 at 01:26:30PM +0200, Michael S. Tsirkin wrote: > > > > No, I am just trying to understand why is hotplug event dangerous. > > > > We still get it if we do device add before starting the VM, right? > > > > > > I'm not sure if it's safe to call enable/disable_device() and > > > pm_update_sci() before starting VM. > > > So I'd like to avoid to call them instead of making sure it. > > > If someone else ensures its safety, I'm willing to eliminate the if > > > clause. > > > > Well I don't think it's dangerous. > > Why?
Because the same effect can be achieved by starting qemu with vm stopped, adding device, then starting qemu. > > I guess it makes sense for whatever is supplied on qemu command line > > to not cause a hotplug event. > > But, those functions inject a hot plug event into a guest. That's why I think your patch is correct. Just the comment is a bit misleading in saying it's dangerous. It's just more correct without the event. > -- > yamahata
