[PATCH v1 2/4] qemu_domain.c: do not launch ppc64 guests with 'pvspinlock' setting

[Daniel Henrique Barboza <danielhb413@xxxxxxxxx>]

PowerPC does not support the 'pvspinlock' feature. The "<pvspinlock/>"
declaration will always have a value 'on' or 'off', and both will
break QEMU when launching. This is the error message for
"<pvspinlock state='on'/>":

qemu-kvm: Expected key=value format, found +kvm_pv_unhalt

A similar error message is thrown for "<pvspinlock state='off'/>".

This patch prevents the pseries guest from launching with any
pvspinlock setting with a more informative error message:

error: unsupported configuration: The 'pvspinlock' feature is not
supported for architecture 'ppc64' or machine type 'pseries'

Signed-off-by: Daniel Henrique Barboza <danielhb413@xxxxxxxxx>
---
 src/qemu/qemu_domain.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 381b62b96a..c67abec778 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -5281,13 +5281,25 @@ qemuDomainDefValidateFeatures(const virDomainDef *def,
             }
             break;
 
+        case VIR_DOMAIN_FEATURE_PVSPINLOCK:
+            if (def->features[i] != VIR_TRISTATE_SWITCH_ABSENT &&
+                ARCH_IS_PPC64(def->os.arch)) {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                               _("The '%s' feature is not supported for "
+                                 "architecture '%s' or machine type '%s'"),
+                                 featureName,
+                                 virArchToString(def->os.arch),
+                                 def->os.machine);
+                 return -1;
+            }
+            break;
+
         case VIR_DOMAIN_FEATURE_ACPI:
         case VIR_DOMAIN_FEATURE_PAE:
         case VIR_DOMAIN_FEATURE_HAP:
         case VIR_DOMAIN_FEATURE_VIRIDIAN:
         case VIR_DOMAIN_FEATURE_PRIVNET:
         case VIR_DOMAIN_FEATURE_HYPERV:
-        case VIR_DOMAIN_FEATURE_PVSPINLOCK:
         case VIR_DOMAIN_FEATURE_CAPABILITIES:
         case VIR_DOMAIN_FEATURE_PMU:
         case VIR_DOMAIN_FEATURE_MSRS:
-- 
2.25.1