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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 4/9/26 23:33, Sean Christopherson wrote: > +static inline bool kvm_vcpu_is_runnable_and_scheduled_out(struct kvm_vcpu *vcpu) > +{ > + return READ_ONCE(vcpu->preempted) || > + (READ_ONCE(vcpu->scheduled_out) && > + READ_ONCE(vcpu->wants_to_run) && wants_to_run doesn't seem important here, because blocking will never be set outside KVM_RUN (unlike scheduled_out which can be set within any vcpu_load/vcpu_put pair, if you're unlucky enough). > + READ_ONCE(vcpu->stat.generic.blocking) && > + !kvm_vcpu_is_blocking(vcpu)); If you get here you have done the finish_rcuwait() in kvm_vcpu_block(), meaning that you've been already scheduled in, haven't you? So, you would need something like this: static inline bool kvm_vcpu_is_runnable_and_scheduled_out(struct kvm_vcpu *vcpu) { if (READ_ONCE(vcpu->preempted)) return true; if (!READ_ONCE(vcpu->scheduled_out)) return false; if (!READ_ONCE(vcpu->stat.generic.blocking)) return false; return rcuwait_was_woken(kvm_arch_vcpu_get_wait(vcpu)); } // in rcuwait.h static inline bool rcuwait_was_woken(struct rcuwait *w) { guard(rcu)(); struct task_struct *t = rcu_access_pointer(w->task); return t && !task_is_runnable(t); } Paolo > +} > + > #ifdef __KVM_HAVE_ARCH_INTC_INITIALIZED > /* > * returns true if the virtual interrupt controller is initialized and > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 9faf70ccae7a..9f71e32daac5 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -455,7 +455,6 @@ static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) > kvm_vcpu_set_in_spin_loop(vcpu, false); > kvm_vcpu_set_dy_eligible(vcpu, false); > vcpu->preempted = false; > - vcpu->ready = false; > preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops); > vcpu->last_used_slot = NULL; > > @@ -3803,7 +3802,6 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_vcpu_halt); > bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu) > { > if (__kvm_vcpu_wake_up(vcpu)) { > - WRITE_ONCE(vcpu->ready, true); > ++vcpu->stat.generic.halt_wakeup; > return true; > } > @@ -4008,7 +4006,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode) > continue; > > vcpu = xa_load(&kvm->vcpu_array, idx); > - if (!READ_ONCE(vcpu->ready)) > + if (!kvm_vcpu_is_runnable_and_scheduled_out(vcpu)) > continue; > if (kvm_vcpu_is_blocking(vcpu) && !vcpu_dy_runnable(vcpu)) > continue; > @@ -6393,7 +6391,6 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu) > struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); > > WRITE_ONCE(vcpu->preempted, false); > - WRITE_ONCE(vcpu->ready, false); > > __this_cpu_write(kvm_running_vcpu, vcpu); > kvm_arch_vcpu_load(vcpu, cpu); > @@ -6408,10 +6405,9 @@ static void kvm_sched_out(struct preempt_notifier *pn, > > WRITE_ONCE(vcpu->scheduled_out, true); > > - if (task_is_runnable(current) && vcpu->wants_to_run) { > + if (task_is_runnable(current) && vcpu->wants_to_run) > WRITE_ONCE(vcpu->preempted, true); > - WRITE_ONCE(vcpu->ready, true); > - } > + > kvm_arch_vcpu_put(vcpu); > __this_cpu_write(kvm_running_vcpu, NULL); > } > > base-commit: b89df297a47e641581ee67793592e5c6ae0428f4