From 441e881e9a2382a965eb540fe45df85b3acb4058 Mon Sep 17 00:00:00 2001
From: Cole Robinson <crobinso@redhat.com>
Date: Sun, 24 Apr 2016 19:04:10 -0400
Subject: [PATCH] nwfilter: Save config to disk if we generated a UUID

libvirt-daemon-config-nwfilter will put a bunch of xml configs
into /etc/libvirt/nwfilter. These configs don't hardcode a UUID
and depends on libvirt to generate one. However the generated UUID
is never saved to disk, unless the user manually calls Define.

This makes daemon reload quite noisy with many errors like:

error : virNWFilterObjAssignDef:3101 : operation failed: filter 'allow-incoming-ipv4' already exists with uuid 50def3b5-48d6-46a3-b005-cc22df4e5c5c

Because a new UUID is generated every time the config is read from
disk, so libvirt constantly thinks it's finding a new nwfilter.

Detect if we generated a UUID when the config file is loaded; if so,
resave the new contents to disk to ensure the UUID is persisteny.

This is similar to what was done in commit a47ae7c0 with virtual
networks and generated MAC addresses
---
 src/conf/nwfilter_conf.c | 6 ++++++
 src/conf/nwfilter_conf.h | 1 +
 2 files changed, 7 insertions(+)

diff --git a/src/conf/nwfilter_conf.c b/src/conf/nwfilter_conf.c
index 544a65078a..3f90f65d1f 100644
--- a/src/conf/nwfilter_conf.c
+++ b/src/conf/nwfilter_conf.c
@@ -2658,6 +2658,7 @@ virNWFilterDefParseXML(xmlXPathContextPtr ctxt)
     }
 
     uuid = virXPathString("string(./uuid)", ctxt);
+    ret->uuid_specified = (uuid != NULL);
     if (uuid == NULL) {
         if (virUUIDGenerate(ret->uuid) < 0) {
             virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -3178,6 +3179,11 @@ virNWFilterLoadConfig(virNWFilterObjListPtr nwfilters,
         goto error;
     }
 
+    /* We generated a UUID, make it permanent by saving the config to disk */
+    if (!def->uuid_specified &&
+        virNWFilterSaveConfig(configDir, def) < 0)
+        goto error;
+
     if (!(nwfilter = virNWFilterObjAssignDef(nwfilters, def)))
         goto error;
 
diff --git a/src/conf/nwfilter_conf.h b/src/conf/nwfilter_conf.h
index 823cfa430d..ea3cd5cd74 100644
--- a/src/conf/nwfilter_conf.h
+++ b/src/conf/nwfilter_conf.h
@@ -536,6 +536,7 @@ typedef virNWFilterDef *virNWFilterDefPtr;
 struct _virNWFilterDef {
     char *name;
     unsigned char uuid[VIR_UUID_BUFLEN];
+    bool uuid_specified;
 
     char *chainsuffix;
     virNWFilterChainPriority chainPriority;