On 06/28/2012 09:07 AM, Tomoki Sekiyama wrote: > Add path to migrate execution of vcpu_enter_guest to a slave CPU when > vcpu->arch.slave_cpu is set. > > After moving to the slave CPU, it goes back to the online CPU when the > guest is exited by reasons that cannot be handled by the slave CPU only > (e.g. handling async page faults). What about, say, instruction emulation? It may need to touch guest memory, which cannot be done from interrupt disabled context. > + > +static int vcpu_post_run(struct kvm_vcpu *vcpu, struct task_struct *task, > + int *can_complete_async_pf) > +{ > + int r = LOOP_ONLINE; > + > + clear_bit(KVM_REQ_PENDING_TIMER, &vcpu->requests); > + if (kvm_cpu_has_pending_timer(vcpu)) > + kvm_inject_pending_timer_irqs(vcpu); > + > + if (dm_request_for_irq_injection(vcpu)) { > + r = -EINTR; > + vcpu->run->exit_reason = KVM_EXIT_INTR; > + ++vcpu->stat.request_irq_exits; > + } > + > + if (can_complete_async_pf) { > + *can_complete_async_pf = kvm_can_complete_async_pf(vcpu); > + if (r == LOOP_ONLINE) > + r = *can_complete_async_pf ? LOOP_APF : LOOP_SLAVE; > + } else > + kvm_check_async_pf_completion(vcpu); > + > + if (signal_pending(task)) { > + r = -EINTR; > + vcpu->run->exit_reason = KVM_EXIT_INTR; > + ++vcpu->stat.signal_exits; > + } Isn't this racy? The signal can come right after this. -- 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