qemu: Introduce qemuDomainDefCheckABIStability

https://bugzilla.redhat.com/show_bug.cgi?id=994364

Whenever we check for ABI stability, we have new xml (e.g. provided by
user, or obtained from snapshot, whatever) which we compare to old xml
and see if ABI won't break. However, if the new xml was produced via
virDomainGetXMLDesc(..., VIR_DOMAIN_XML_MIGRATABLE) it lacks some
devices, e.g. 'pci-root' controller. Hence, the ABI stability check
fails even though it is stable. Moreover, we can't simply fix
virDomainDefCheckABIStability because removing the correct devices is
task for the driver. For instance, qemu driver wants to remove the usb
controller too, while LXC driver doesn't. That's why we need special
qemu wrapper over virDomainDefCheckABIStability which removes the
correct devices from domain XML, produces MIGRATABLE xml and calls the
check ABI stability function.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 7d704812b9c50cd3804dd1e7f9e2ea3e75fdc847)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 968e323210b41d2903811f5ddf884607d05e3b06..f3e2ba1cf21648a1c3a7557bdedb029fa09a0a05 100644 (file)
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -2342,3 +2342,25 @@ qemuDomainUpdateDeviceList(virQEMUDriverPtr driver,
     priv->qemuDevices = aliases;
     return 0;
 }
+
+bool
+qemuDomainDefCheckABIStability(virQEMUDriverPtr driver,
+                               virDomainDefPtr src,
+                               virDomainDefPtr dst)
+{
+    virDomainDefPtr migratableDefSrc = NULL;
+    virDomainDefPtr migratableDefDst = NULL;
+    const int flags = VIR_DOMAIN_XML_SECURE | VIR_DOMAIN_XML_UPDATE_CPU | VIR_DOMAIN_XML_MIGRATABLE;
+    bool ret = false;
+
+    if (!(migratableDefSrc = qemuDomainDefCopy(driver, src, flags)) ||
+        !(migratableDefDst = qemuDomainDefCopy(driver, dst, flags)))
+        goto cleanup;
+
+    ret = virDomainDefCheckABIStability(migratableDefSrc, migratableDefDst);
+
+cleanup:
+    virDomainDefFree(migratableDefSrc);
+    virDomainDefFree(migratableDefDst);
+    return ret;
+}

diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index 04f08a3784dfa315afc8a73f77a3f0b52d6370fb..77e0c20171ed5261751686997865c409f19722d9 100644 (file)
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -369,4 +369,7 @@ extern virDomainDefParserConfig virQEMUDriverDomainDefParserConfig;
 int qemuDomainUpdateDeviceList(virQEMUDriverPtr driver,
                                virDomainObjPtr vm);
 
+bool qemuDomainDefCheckABIStability(virQEMUDriverPtr driver,
+                                    virDomainDefPtr src,
+                                    virDomainDefPtr dst);
 #endif /* __QEMU_DOMAIN_H__ */

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 58be3085759c07adaaec4b2d18e9e82a23e2e83f..d7f92f4521de0345ed99c2cba5c3e061af687c62 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -3085,7 +3085,7 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver, virDomainPtr dom,
                                             VIR_DOMAIN_XML_INACTIVE))) {
             goto endjob;
         }
-        if (!virDomainDefCheckABIStability(vm->def, def)) {
+        if (!qemuDomainDefCheckABIStability(driver, vm->def, def)) {
             virDomainDefFree(def);
             goto endjob;
         }
@@ -13030,7 +13030,6 @@ static int qemuDomainRevertToSnapshot(virDomainSnapshotPtr snapshot,
     qemuDomainObjPrivatePtr priv;
     int rc;
     virDomainDefPtr config = NULL;
-    virDomainDefPtr migratableDef = NULL;
     virQEMUDriverConfigPtr cfg = NULL;
     virCapsPtr caps = NULL;
 
@@ -13147,11 +13146,7 @@ static int qemuDomainRevertToSnapshot(virDomainSnapshotPtr snapshot,
             /* Transitions 5, 6, 8, 9 */
             /* Check for ABI compatibility. We need to do this check against
              * the migratable XML or it will always fail otherwise */
-            if (!(migratableDef = qemuDomainDefCopy(driver, vm->def,
-                                                    VIR_DOMAIN_XML_MIGRATABLE)))
-                goto cleanup;
-
-            if (config && !virDomainDefCheckABIStability(migratableDef, config)) {
+            if (config && !qemuDomainDefCheckABIStability(driver, vm->def, config)) {
                 virErrorPtr err = virGetLastError();
 
                 if (!(flags & VIR_DOMAIN_SNAPSHOT_REVERT_FORCE)) {
@@ -13356,7 +13351,6 @@ cleanup:
     }
     if (vm)
         virObjectUnlock(vm);
-    virDomainDefFree(migratableDef);
     virObjectUnref(caps);
     virObjectUnref(cfg);
 

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 58f90c28856dae824435bad9f5bf4f43cd073491..2db5ed083f030b5715e6b2ecdfb8d508c2419519 100644 (file)
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -2043,7 +2043,7 @@ static char
                                             VIR_DOMAIN_XML_INACTIVE)))
             goto cleanup;
 
-        if (!virDomainDefCheckABIStability(vm->def, def))
+        if (!qemuDomainDefCheckABIStability(driver, vm->def, def))
             goto cleanup;
 
         rv = qemuDomainDefFormatLive(driver, def, false, true);
@@ -2250,7 +2250,7 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                 if (!newdef)
                     goto cleanup;
 
-                if (!virDomainDefCheckABIStability(*def, newdef)) {
+                if (!qemuDomainDefCheckABIStability(driver, *def, newdef)) {
                     virDomainDefFree(newdef);
                     goto cleanup;
                 }