On 28/12/2022 12:04, Paolo Bonzini wrote: > While KVM_XEN_EVTCHN_RESET is usually called with no vCPUs running, > if that happened it could cause a deadlock. This is due to > kvm_xen_eventfd_reset() doing a synchronize_srcu() inside > a kvm->lock critical section. > > [...] > > + /* > + * Because synchronize_srcu() cannot be called inside the > + * critical section, first collect all the evtchnfd objects > + * in an array as they are removed from evtchn_ports. > + */ With the recent changes regarding the locking order (locking.rst: "synchronize_srcu(&kvm->srcu) is called inside critical sections for kvm->lock, vcpu->mutex and kvm->slots_lock"), is this comment still valid? Or is there a rule that forbids synchronize_srcu() under the newly introduced kvm->arch.xen.xen_lock? thanks, Michal
