On Wed, Nov 30, 2011 at 02:51:06PM +0100, Christophe Fergeau wrote:
This method starts by looking up a domain in priv->domains, and
later,
depending on the kind of event that occurred, it may remove this
domain from priv->domains. While the individual operations (lookup,
removal) are protected by priv->lock, there is no guarantee that the
looked up domain and even priv->domains will stay unchanged when
priv->lock isn't held.
In particular, gvir_connection_close will destroy priv->domains which
will unreference all the domains it contains (potentially destroying
them too), and gvir_connection_fetch_domains will change priv->domains
value.
To avoid these issues, this commit takes a reference on priv->domains
so that it doesn't get away behind our back, and it takes a reference
on the looked up domain too to ensure it stays alive for the duration
of domain_event_cb run.
---
libvirt-gobject/libvirt-gobject-connection.c | 17 +++++++++++------
1 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/libvirt-gobject/libvirt-gobject-connection.c
b/libvirt-gobject/libvirt-gobject-connection.c
index 59b828d..786a026 100644
--- a/libvirt-gobject/libvirt-gobject-connection.c
+++ b/libvirt-gobject/libvirt-gobject-connection.c
@@ -257,6 +257,7 @@ static int domain_event_cb(virConnectPtr conn G_GNUC_UNUSED,
void *opaque)
{
gchar uuid[VIR_UUID_STRING_BUFLEN];
+ GHashTable *doms;
GVirConnection *gconn = opaque;
GVirDomain *gdom;
GVirConnectionPrivate *priv = gconn->priv;
@@ -269,14 +270,18 @@ static int domain_event_cb(virConnectPtr conn G_GNUC_UNUSED,
g_debug("%s: %s event:%d, detail:%d", G_STRFUNC, uuid, event, detail);
g_mutex_lock(priv->lock);
- gdom = g_hash_table_lookup(priv->domains, uuid);
+ doms = g_hash_table_ref(priv->domains);
+ gdom = g_hash_table_lookup(doms, uuid);
+ if (gdom != NULL)
+ g_object_ref(G_OBJECT(gdom));
g_mutex_unlock(priv->lock);
if (gdom == NULL) {
gdom = GVIR_DOMAIN(g_object_new(GVIR_TYPE_DOMAIN, "handle", dom,
NULL));
g_mutex_lock(priv->lock);
- g_hash_table_insert(priv->domains, (gpointer)gvir_domain_get_uuid(gdom),
gdom);
+ g_hash_table_insert(doms, (gpointer)gvir_domain_get_uuid(gdom),
+ g_object_ref(G_OBJECT(gdom)));
g_mutex_unlock(priv->lock);
}
@@ -293,11 +298,10 @@ static int domain_event_cb(virConnectPtr conn G_GNUC_UNUSED,
case VIR_DOMAIN_EVENT_UNDEFINED:
if (detail == VIR_DOMAIN_EVENT_UNDEFINED_REMOVED) {
g_mutex_lock(priv->lock);
- g_hash_table_steal(priv->domains, uuid);
+ g_hash_table_remove(doms, uuid);
g_mutex_unlock(priv->lock);
g_signal_emit(gconn, signals[VIR_DOMAIN_REMOVED], 0, gdom);
- g_object_unref(gdom);
} else
g_warn_if_reached();
break;
@@ -365,11 +369,10 @@ static int domain_event_cb(virConnectPtr conn G_GNUC_UNUSED,
if (virDomainIsPersistent(dom) != 1) {
g_mutex_lock(priv->lock);
- g_hash_table_steal(priv->domains, uuid);
+ g_hash_table_remove(doms, uuid);
g_mutex_unlock(priv->lock);
g_signal_emit(gconn, signals[VIR_DOMAIN_REMOVED], 0, gdom);
- g_object_unref(gdom);
}
break;
@@ -377,6 +380,8 @@ static int domain_event_cb(virConnectPtr conn G_GNUC_UNUSED,
g_warn_if_reached();
}
+ g_object_unref(G_OBJECT(gdom));
+ g_hash_table_unref(doms);
return 0;
}
ACK
Daniel
--
|:
http://berrange.com -o-
http://www.flickr.com/photos/dberrange/ :|
|:
http://libvirt.org -o-
http://virt-manager.org :|
|:
http://autobuild.org -o-
http://search.cpan.org/~danberr/ :|
|:
http://entangle-photo.org -o-
http://live.gnome.org/gtk-vnc :|