diff --git a/hw/intc/xics_kvm.c b/hw/intc/xics_kvm.c index a1f1b7b0d3..8d6156578f 100644 --- a/hw/intc/xics_kvm.c +++ b/hw/intc/xics_kvm.c @@ -165,8 +165,15 @@ void icp_kvm_realize(DeviceState *dev, Error **errp) ret = kvm_vcpu_enable_cap(cs, KVM_CAP_IRQ_XICS, 0, kernel_xics_fd, vcpu_id); if (ret < 0) { - error_setg(errp, "Unable to connect CPU%ld to kernel XICS: %s", vcpu_id, - strerror(errno)); + Error *local_err = NULL; + + error_setg(&local_err, "Unable to connect CPU%ld to kernel XICS: %s", + vcpu_id, strerror(errno)); + if (errno == ENOSPC) { + error_append_hint(&local_err, "Try -smp maxcpus=N with N < %u\n", + MACHINE(qdev_get_machine())->smp.max_cpus); + } + error_propagate(errp, local_err); return; } enabled_icp = g_malloc(sizeof(*enabled_icp)); @@ -399,6 +406,16 @@ int xics_kvm_connect(SpaprInterruptController *intc, uint32_t nr_servers, goto fail; } + /* Tell KVM about the # of VCPUs we may have (POWER9 and newer only) */ + if (kvm_device_check_attr(rc, KVM_DEV_XICS_GRP_CTRL, + KVM_DEV_XICS_NR_SERVERS)) { + if (kvm_device_access(rc, KVM_DEV_XICS_GRP_CTRL, + KVM_DEV_XICS_NR_SERVERS, &nr_servers, true, + &local_err)) { + goto fail; + } + } + kernel_xics_fd = rc; kvm_kernel_irqchip = true; kvm_msi_via_irqfd_allowed = true;