qemu: Pass qemuCaps to qemuMigrationAnyPrepareDef

Since qemuDomainDefPostParse callback requires qemuCaps, we need to make
sure it gets the capabilities stored in the domain's private data if the
domain is running. Passing NULL may cause QEMU capabilities probing to
be triggered in case QEMU binary changed in the meantime. When this
happens while a running domain object is locked, QMP event delivered to
the domain before QEMU capabilities probing finishes will deadlock the
event loop.

This patch fixes all paths leading to qemuMigrationAnyPrepareDef.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_driver.c

@@ -12651,7 +12651,7 @@ qemuDomainMigratePrepareTunnel(virConnectPtr dconn,
         goto cleanup;
     }
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepareTunnelEnsureACL(dconn, def) < 0)
@@ -12712,7 +12712,7 @@ qemuDomainMigratePrepare2(virConnectPtr dconn,
         goto cleanup;
     }
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepare2EnsureACL(dconn, def) < 0)
@@ -12951,7 +12951,7 @@ qemuDomainMigratePrepare3(virConnectPtr dconn,
                                                    QEMU_MIGRATION_DESTINATION)))
         goto cleanup;
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepare3EnsureACL(dconn, def) < 0)
@@ -13038,7 +13038,7 @@ qemuDomainMigratePrepare3Params(virConnectPtr dconn,
         goto cleanup;
     }
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepare3ParamsEnsureACL(dconn, def) < 0)
@@ -13092,7 +13092,7 @@ qemuDomainMigratePrepareTunnel3(virConnectPtr dconn,
                                                    QEMU_MIGRATION_DESTINATION)))
         goto cleanup;
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepareTunnel3EnsureACL(dconn, def) < 0)
@@ -13151,7 +13151,7 @@ qemuDomainMigratePrepareTunnel3Params(virConnectPtr dconn,
                                                    QEMU_MIGRATION_DESTINATION)))
         goto cleanup;
 
-    if (!(def = qemuMigrationAnyPrepareDef(driver, dom_xml, dname, &origname)))
+    if (!(def = qemuMigrationAnyPrepareDef(driver, NULL, dom_xml, dname, &origname)))
         goto cleanup;
 
     if (virDomainMigratePrepareTunnel3ParamsEnsureACL(dconn, def) < 0)

src/qemu/qemu_migration.c

@@ -2861,6 +2861,7 @@ qemuMigrationDstPrepareDirect(virQEMUDriverPtr driver,
 
 virDomainDefPtr
 qemuMigrationAnyPrepareDef(virQEMUDriverPtr driver,
+                           virQEMUCapsPtr qemuCaps,
                            const char *dom_xml,
                            const char *dname,
                            char **origname)
@@ -2878,7 +2879,8 @@ qemuMigrationAnyPrepareDef(virQEMUDriverPtr driver,
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         return NULL;
 
-    if (!(def = virDomainDefParseString(dom_xml, caps, driver->xmlopt, NULL,
+    if (!(def = virDomainDefParseString(dom_xml, caps, driver->xmlopt,
+                                        qemuCaps,
                                         VIR_DOMAIN_DEF_PARSE_INACTIVE |
                                         VIR_DOMAIN_DEF_PARSE_SKIP_VALIDATE)))
         goto cleanup;
@@ -3422,7 +3424,9 @@ qemuMigrationSrcRun(virQEMUDriverPtr driver,
 
     if (flags & VIR_MIGRATE_PERSIST_DEST) {
         if (persist_xml) {
-            if (!(persistDef = qemuMigrationAnyPrepareDef(driver, persist_xml,
+            if (!(persistDef = qemuMigrationAnyPrepareDef(driver,
+                                                          priv->qemuCaps,
+                                                          persist_xml,
                                                           NULL, NULL)))
                 goto error;
         } else {

src/qemu/qemu_migration.h

@@ -115,6 +115,7 @@ qemuMigrationSrcBegin(virConnectPtr conn,
 
 virDomainDefPtr
 qemuMigrationAnyPrepareDef(virQEMUDriverPtr driver,
+                           virQEMUCapsPtr qemuCaps,
                            const char *dom_xml,
                            const char *dname,
                            char **origname);