Commit c896939f7cff ("KVM: use heuristic for fast VCPU lookup by id") added a return path that prevents vcpu ids to exceed KVM_MAX_VCPUS. This is a problem for powerpc where vcpu ids can grow up to 8*KVM_MAX_VCPUS. This patch simply reverses the logic so that we only try fast path if the vcpu id can be tried as an index in kvm->vcpus[]. The slow path is not affected by the change. Reviewed-by: David Hildenbrand <dahi@xxxxxxxxxxxxxxxxxx> Reviewed-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> Signed-off-by: Greg Kurz <gkurz@xxxxxxxxxxxxxxxxxx> --- v5: - added David's and Conny's R-b tags --- include/linux/kvm_host.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 5276fe0916fc..23bfe1bd159c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -447,12 +447,13 @@ static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i) static inline struct kvm_vcpu *kvm_get_vcpu_by_id(struct kvm *kvm, int id) { - struct kvm_vcpu *vcpu; + struct kvm_vcpu *vcpu = NULL; int i; - if (id < 0 || id >= KVM_MAX_VCPUS) + if (id < 0) return NULL; - vcpu = kvm_get_vcpu(kvm, id); + if (id < KVM_MAX_VCPUS) + vcpu = kvm_get_vcpu(kvm, id); if (vcpu && vcpu->vcpu_id == id) return vcpu; kvm_for_each_vcpu(i, vcpu, kvm)