SUSE adjustments to qemu.conf

This patch contains SUSE-specific adjustments to the upstream
qemu.conf configuration file. In the future, it might make
sense to separate these changes into individual patches (e.g.
suse-qemu-conf-secdriver.patch, suse-qemu-conf-lockmgr.patch,
etc.), but for now they are all lumped together in this
single patch.

Index: libvirt-3.9.0/src/qemu/qemu.conf
===================================================================
--- libvirt-3.9.0.orig/src/qemu/qemu.conf
+++ libvirt-3.9.0/src/qemu/qemu.conf
@@ -380,11 +380,20 @@
 # isolation, but it cannot appear in a list of drivers.
 #
 #security_driver = "selinux"
+#security_driver = "apparmor"
 
 # If set to non-zero, then the default security labeling
 # will make guests confined. If set to zero, then guests
-# will be unconfined by default. Defaults to 1.
-#security_default_confined = 1
+# will be unconfined by default. Defaults to 0.
+#
+# SUSE Note:
+# Currently, Apparmor is the default security framework in SUSE
+# distros.  If Apparmor is enabled on the host, libvirtd is
+# generously confined but users must opt-in to confine qemu
+# instances.  Change this to a non-zero value to enable default
+# Apparmor confinement of qemu instances.
+#
+security_default_confined = 0
 
 # If set to non-zero, then attempts to create unconfined
 # guests will be blocked. Defaults to 0.
@@ -628,11 +637,22 @@
 #allow_disk_format_probing = 1
 
 
-# In order to prevent accidentally starting two domains that
-# share one writable disk, libvirt offers two approaches for
-# locking files. The first one is sanlock, the other one,
-# virtlockd, is then our own implementation. Accepted values
-# are "sanlock" and "lockd".
+# SUSE note:
+# Two lock managers are supported: lockd and sanlock.  lockd, which
+# is provided by the virtlockd service, uses advisory locks (flock(2))
+# to protect virtual machine disks.  sanlock uses the notion of leases
+# to protect virtual machine disks and is more appropriate in a SAN
+# environment.
+#
+# For most deployments that require virtual machine disk protection,
+# lockd is recommended since it is easy to configure and the virtlockd
+# service can be restarted without terminating any running virtual
+# machines.  sanlock, which may be preferred in some SAN environments,
+# has the disadvantage of not being able to be restarted without
+# first terminating all virtual machines for which it holds leases.
+#
+# Specify lockd or sanlock to enable protection of virtual machine disk
+# content.
 #
 #lock_manager = "lockd"