On Mon, Feb 19, 2018 at 4:13 PM, Alan Cox <gnomes@xxxxxxxxxxxxxxxxxxx> wrote: > > In theory there's nothing stopping a guest getting a 'you are about to > gain/lose IBRS' message or having a new 'CPU' hotplugged and the old one > removed. I'm not convinced we handle the case of hotplug CPU's with different CPU models correctly. In fact, I'd be very surprised it it worked in the general case. Linus