Hi Xiantao, On Wed, Oct 15, 2008 at 09:47:24PM +0800, Zhang, Xiantao wrote: > + expires = div64_u64(itc_diff, cyc_per_usec); > + kt = ktime_set(0, 1000 * expires); > + > + down_read(&vcpu->kvm->slots_lock); > + vcpu->arch.ht_active = 1; > + hrtimer_start(p_ht, kt, HRTIMER_MODE_ABS); > > - if (irqchip_in_kernel(vcpu->kvm)) { > vcpu->arch.mp_state = KVM_MP_STATE_HALTED; > kvm_vcpu_block(vcpu); > hrtimer_cancel(p_ht); > vcpu->arch.ht_active = 0; > > + if (test_and_clear_bit(KVM_REQ_UNHALT, &vcpu->requests)) > + if (vcpu->arch.mp_state == KVM_MP_STATE_HALTED) > + vcpu->arch.mp_state = > + KVM_MP_STATE_RUNNABLE; > + up_read(&vcpu->kvm->slots_lock); You should release slots_lock when blocking via kvm_vcpu_block(). Otherwise paths that grab it for write will depend on these vcpus to unhalt. BTW, none of the data structures in this section of code should be protected by slots_lock? -- To unsubscribe from this list: send the line "unsubscribe kvm-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html