hw/s390x: Remove the cpu_model_allowed flag and related code

Now that the last machine type that disabled cpu_model_allowed has
been removed, we can also remove the cpu_model_allowed flag itself
and all the related conditional code.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Message-ID: <20250103144232.520383-9-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

hw/s390x/s390-virtio-ccw.c

@@ -727,8 +727,7 @@ static S390CcwMachineClass *current_mc;
  *
  * Attention! Do *not* add additional new wrappers for CPU features via this
  * mechanism anymore. CPU features should be handled via the CPU models,
- * i.e. checking with cpu_model_allowed() during CPU initialization and
- * s390_has_feat() later should be sufficient.
+ * i.e. checking with s390_has_feat() should be sufficient.
  */
 static S390CcwMachineClass *get_machine_class(void)
 {
@@ -744,11 +743,6 @@ static S390CcwMachineClass *get_machine_class(void)
     return current_mc;
 }
 
-bool cpu_model_allowed(void)
-{
-    return get_machine_class()->cpu_model_allowed;
-}
-
 bool hpage_1m_allowed(void)
 {
     return get_machine_class()->hpage_1m_allowed;
@@ -786,7 +780,6 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
     S390CcwMachineClass *s390mc = S390_CCW_MACHINE_CLASS(mc);
 
-    s390mc->cpu_model_allowed = true;
     s390mc->hpage_1m_allowed = true;
     s390mc->max_threads = 1;
     mc->init = ccw_init;

include/hw/s390x/s390-virtio-ccw.h

@@ -53,13 +53,10 @@ struct S390CcwMachineClass {
     MachineClass parent_class;
 
     /*< public >*/
-    bool cpu_model_allowed;
     bool hpage_1m_allowed;
     int max_threads;
 };
 
-/* cpu model allowed by the machine */
-bool cpu_model_allowed(void);
 /* 1M huge page mappings allowed by the machine */
 bool hpage_1m_allowed(void);
 

target/s390x/kvm/kvm.c

@@ -374,12 +374,10 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     kvm_vm_enable_cap(s, KVM_CAP_S390_VECTOR_REGISTERS, 0);
     kvm_vm_enable_cap(s, KVM_CAP_S390_USER_STSI, 0);
     kvm_vm_enable_cap(s, KVM_CAP_S390_CPU_TOPOLOGY, 0);
+    kvm_vm_enable_cap(s, KVM_CAP_S390_GS, 0);
     if (kvm_vm_enable_cap(s, KVM_CAP_S390_RI, 0) == 0) {
         cap_ri = 1;
     }
-    if (cpu_model_allowed()) {
-        kvm_vm_enable_cap(s, KVM_CAP_S390_GS, 0);
-    }
 
     /*
      * The migration interface for ais was introduced with kernel 4.13
@@ -387,7 +385,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
      * support is considered necessary, we only try to enable this for
      * newer machine types if KVM_CAP_S390_AIS_MIGRATION is available.
      */
-    if (cpu_model_allowed() && kvm_kernel_irqchip_allowed() &&
+    if (kvm_kernel_irqchip_allowed() &&
         kvm_check_extension(s, KVM_CAP_S390_AIS_MIGRATION)) {
         kvm_vm_enable_cap(s, KVM_CAP_S390_AIS, 0);
     }
@@ -2352,10 +2350,6 @@ static int configure_cpu_feat(const S390FeatBitmap features)
 
 bool kvm_s390_cpu_models_supported(void)
 {
-    if (!cpu_model_allowed()) {
-        /* compatibility machines interfere with the cpu model */
-        return false;
-    }
     return kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,
                              KVM_S390_VM_CPU_MACHINE) &&
            kvm_vm_check_attr(kvm_state, KVM_S390_VM_CPU_MODEL,