target-i386: Fix X86CPU error handling

Error **errp argument is not for emitting warnings, it means an error
has occurred and the caller should not make any assumptions about the
state of other return values (unless otherwise documented).

Therefore cpu_x86_create() must unref the new X86CPU itself, and
pc_new_cpu() must check for an Error rather than NULL return value.

While at it, clean up a superfluous NULL check.

Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: qemu-stable@nongnu.org
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from commit cd7b87ffe9b6b7b0089ec8c71555f3b942bc6daf)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index e2c44f888201af087586ed4466a14787c2758b3c..a7ecfb0586a3663a7f9b0f8c535b47a89fafb9d5 100644 (file)
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -902,20 +902,19 @@ static X86CPU *pc_new_cpu(const char *cpu_model, int64_t apic_id,
     X86CPU *cpu;
     Error *local_err = NULL;
 
-    cpu = cpu_x86_create(cpu_model, icc_bridge, errp);
-    if (!cpu) {
-        return cpu;
+    cpu = cpu_x86_create(cpu_model, icc_bridge, &local_err);
+    if (local_err != NULL) {
+        error_propagate(errp, local_err);
+        return NULL;
     }
 
     object_property_set_int(OBJECT(cpu), apic_id, "apic-id", &local_err);
     object_property_set_bool(OBJECT(cpu), true, "realized", &local_err);
 
     if (local_err) {
-        if (cpu != NULL) {
-            object_unref(OBJECT(cpu));
-            cpu = NULL;
-        }
         error_propagate(errp, local_err);
+        object_unref(OBJECT(cpu));
+        cpu = NULL;
     }
     return cpu;
 }

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index ae8e68271b027804ab3e86e96c17556d0ad513a7..cdae1cea581c57d3d45e2e31ab2cf481ed733996 100644 (file)
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1820,7 +1820,11 @@ X86CPU *cpu_x86_create(const char *cpu_model, DeviceState *icc_bridge,
     }
 
 out:
-    error_propagate(errp, error);
+    if (error != NULL) {
+        error_propagate(errp, error);
+        object_unref(OBJECT(cpu));
+        cpu = NULL;
+    }
     g_strfreev(model_pieces);
     return cpu;
 }