On Fri, May 22, 2009 at 02:41:20PM +0300, Gleb Natapov wrote: > On Thu, May 21, 2009 at 05:29:57PM -0300, Marcelo Tosatti wrote: > > On Thu, May 21, 2009 at 11:06:42PM +0300, Gleb Natapov wrote: > > > > Why don't make a convention that vcpu_id 0 is the BSP, by default, > > > > instead of the first vcpu created? This way if userspace creates vcpu 3 > > > > first, there are no problems. > > > > > > > Because userspace no longer control vcpu_id allocation. I also want to > > > get rid of "first vcpu is bsp" restriction, but this fill require new > > > ioctl I guess. > > > > Or hardcode "apic_id == 0 is BSP" for now, and later add an ioctl to set > > the BSP? > > > We should not assume anything about apic_ids. For instance if the number > of ioapics+cpu cores are greater than 15 it is recommended to assign ids > 0-(N-1) to ioapic (N is the number of ioapics). This is because ioapic > id is only 4 bits long, but it occupies the same id space as apic ids. If keep the behaviour like in the last patch submitted, and introduce a new ioctl to set the BSP, you get backward compatibility for free. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html