[Qemu-devel] [PULL v2 21/38] s390x: allow only 1 CPU with TCG

[Cornelia Huck]

From: David Hildenbrand <address@hidden>

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the
guest tries to bring these CPUs up but fails), because we don't support
multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's
hope.

Tested-by: Matthew Rosato <address@hidden>
Signed-off-by: David Hildenbrand <address@hidden>
Message-Id: <address@hidden>
Reviewed-by: Igor Mammedov <address@hidden>
Signed-off-by: Cornelia Huck <address@hidden>
---
 hw/s390x/s390-virtio-ccw.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index c908f63543..56f8200851 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -55,6 +56,11 @@ static void s390_init_cpus(MachineState *machine)
     if (machine->cpu_model == NULL) {
         machine->cpu_model = s390_default_cpu_model_name();
     }
+    if (tcg_enabled() && max_cpus > 1) {
+        error_report("Number of SMP CPUs requested (%d) exceeds max CPUs "
+                     "supported by TCG (1) on s390x", max_cpus);
+        exit(1);
+    }
 
     cpu_states = g_new0(S390CPU *, max_cpus);
 
-- 
2.13.5