- Fix libvirtd deadlock on shutdown

0dda594d-libvirtd-shutdown-deadlock.patch
  bnc#767797

OBS-URL: https://build.opensuse.org/package/show/Virtualization/libvirt?expand=0&rev=215

0dda594d-libvirtd-shutdown-deadlock.patch

@@ -0,0 +1,45 @@
+commit 0dda594da99aede7621018a3705e7cf4c13b1606
+Author: Jim Fehlig <jfehlig@suse.com>
+Date:   Thu Jun 21 09:21:44 2012 -0600
+
+    Fix deadlock on libvirtd shutdown
+    
+    When shutting down libvirtd, the virNetServer shutdown can deadlock
+    if there are in-flight jobs being handled by virNetServerHandleJob().
+    virNetServerFree() will acquire the virNetServer lock and call
+    virThreadPoolFree() to terminate the workers, waiting for the workers
+    to finish.  But in-flight workers will attempt to acquire the
+    virNetServer lock, resulting in deadlock.
+    
+    Fix the deadlock by unlocking the virNetServer lock before calling
+    virThreadPoolFree().  This is safe since the virNetServerPtr object
+    is ref-counted and only decrementing the ref count needs to be
+    protected.  Additionally, there is no need to re-acquire the lock
+    after virThreadPoolFree() completes as all the workers have
+    terminated.
+
+Index: libvirt-0.9.11.4/src/rpc/virnetserver.c
+===================================================================
+--- libvirt-0.9.11.4.orig/src/rpc/virnetserver.c
++++ libvirt-0.9.11.4/src/rpc/virnetserver.c
+@@ -801,10 +801,9 @@ void virNetServerFree(virNetServerPtr sr
+     virNetServerLock(srv);
+     VIR_DEBUG("srv=%p refs=%d", srv, srv->refs);
+     srv->refs--;
+-    if (srv->refs > 0) {
+-        virNetServerUnlock(srv);
++    virNetServerUnlock(srv);
++    if (srv->refs > 0)
+         return;
+-    }
+ 
+     for (i = 0 ; i < srv->nservices ; i++)
+         virNetServerServiceToggle(srv->services[i], false);
+@@ -845,7 +844,6 @@ void virNetServerFree(virNetServerPtr sr
+         dbus_connection_unref(srv->sysbus);
+ #endif
+ 
+-    virNetServerUnlock(srv);
+     virMutexDestroy(&srv->lock);
+     VIR_FREE(srv);
+ }

libvirt.changes

@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Thu Jun 21 11:56:35 MDT 2012 - jfehlig@suse.com
+
+- Fix libvirtd deadlock on shutdown
+  0dda594d-libvirtd-shutdown-deadlock.patch
+  bnc#767797
+
 -------------------------------------------------------------------
 Wed Jun 20 23:40:14 MDT 2012 - jfehlig@suse.com
 

libvirt.spec

@@ -413,6 +413,7 @@ Source99:       baselibs.conf
 # Revert v0.9.11-maint branch commit d8978c90
 Patch0:         revert-d8978c90.patch
 Patch1:         57349ffc-lxc-ctrl.patch
+Patch2:         0dda594d-libvirtd-shutdown-deadlock.patch
 # Need to go upstream
 Patch100:       xen-name-for-devid.patch
 Patch101:       clone.patch
@@ -550,6 +551,7 @@ Authors:
 %setup -q
 %patch0 -p1
 %patch1 -p1
+%patch2 -p1
 %patch100 -p1
 %patch101
 %patch102 -p1