virQEMUDriverDomainABIStability: Check for memoryBacking

https://bugzilla.redhat.com/show_bug.cgi?id=1450349

Problem is, qemu fails to load guest memory image if these
attribute change on migration/restore from an image.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

src/libvirt_private.syms

@@ -409,6 +409,8 @@ virDomainMemoryFindByDef;
 virDomainMemoryFindInactiveByDef;
 virDomainMemoryInsert;
 virDomainMemoryRemove;
+virDomainMemorySourceTypeFromString;
+virDomainMemorySourceTypeToString;
 virDomainNetAppendIPAddress;
 virDomainNetDefClear;
 virDomainNetDefFormat;

src/qemu/qemu_conf.c

@@ -910,7 +910,7 @@ virQEMUDriverCreateXMLConf(virQEMUDriverPtr driver)
     return virDomainXMLOptionNew(&virQEMUDriverDomainDefParserConfig,
                                  &virQEMUDriverPrivateDataCallbacks,
                                  &virQEMUDriverDomainXMLNamespace,
-                                 NULL);
+                                 &virQEMUDriverDomainABIStability);
 }
 
 

src/qemu/qemu_domain.c

@@ -5820,6 +5820,28 @@ qemuDomainUpdateMemoryDeviceInfo(virQEMUDriverPtr driver,
 }
 
 
+static bool
+qemuDomainABIStabilityCheck(const virDomainDef *src,
+                            const virDomainDef *dst)
+{
+    if (src->mem.source != dst->mem.source) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                       _("Target memoryBacking source '%s' doesn't "
+                         "match source memoryBacking source'%s'"),
+                       virDomainMemorySourceTypeToString(dst->mem.source),
+                       virDomainMemorySourceTypeToString(src->mem.source));
+        return false;
+    }
+
+    return true;
+}
+
+
+virDomainABIStability virQEMUDriverDomainABIStability = {
+    .domain = qemuDomainABIStabilityCheck,
+};
+
+
 bool
 qemuDomainDefCheckABIStability(virQEMUDriverPtr driver,
                                virDomainDefPtr src,

src/qemu/qemu_domain.h

@@ -636,6 +636,7 @@ void qemuDomainCleanupRun(virQEMUDriverPtr driver,
 extern virDomainXMLPrivateDataCallbacks virQEMUDriverPrivateDataCallbacks;
 extern virDomainXMLNamespace virQEMUDriverDomainXMLNamespace;
 extern virDomainDefParserConfig virQEMUDriverDomainDefParserConfig;
+extern virDomainABIStability virQEMUDriverDomainABIStability;
 
 int qemuDomainUpdateDeviceList(virQEMUDriverPtr driver,
                                virDomainObjPtr vm, int asyncJob);