On 12/21/2011 12:41 PM, Jan Kiszka wrote: > On 2011-12-21 11:35, Avi Kivity wrote: > > On 12/21/2011 12:25 PM, Jan Kiszka wrote: > >> We must not report the TSC deadline timer feature on our own when user > >> space provides the APIC as we have no clue about its features. > > > > We must not report the TSC deadline timer feature on our own, period. > > We should just update the timer mode mask there. Don't know how this > > slipped through review. > > > > I think your original idea was correct. Add a new KVM_CAP for the tsc > > deadline timer. Userspace can add the bit to cpuid if either it > > implements the feature in a userspace apic, or if it finds the new > > capability and uses the kernel apic. > > Right, we do need some control for user space to keep the feature > disabled when migrating from an older host. > > However, there is also the timer_mode_mask which requires tuning in > addition to the cpuid flag. > timer_mode_mask can just be slaved to the bit (as received by KVM_SET_CPUID); that's exactly kvm_update_cpuid()'s role. -- error compiling committee.c: too many arguments to function -- 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
