+++ This bug was initially created as a clone of Bug #1025230 +++

Description of problem:
libvirt activate pool with invalid source.

Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux Server release 7.0 Beta
libvirt-1.1.1-10.el7.x86_64

How reproducible:
always

Command:
1. Define a pool with an invalid source.
# cat test_pool.xml 
<pool type='fs'>
  <name>test_pool</name>
  <source>
    <device path='/dev/notexist'/>
    <format type='ext3'/>
  </source>
  <target>
    <path>/mnt</path>
    <permissions>
      <mode>0777</mode>
      <owner>0</owner>
      <group>0</group>
    </permissions>
  </target>
</pool>

# virsh pool-define test_pool.xml

2. Try to start the pool.
# virsh pool-start test_pool
error: Failed to start pool test_pool
error: internal error: Child process (/usr/bin/mount -t ext3 /dev/notexist /mnt) unexpected exit status 32: mount: special device /dev/notexist does not exist

# virsh pool-list --all
Name                 State      Autostart 
-----------------------------------------
default              active     yes       
test_pool            inactive   no   

3. Mount a valid fs to target path.
# mount /dev/sda1 /mnt

4. Restart libvirt daemon.
# service libvirtd restart

5. The invalid pool is active.
# virsh pool-list --all
Name                 State      Autostart 
-----------------------------------------
default              active     yes       
test_pool            active     no    

Expected result:
The pool with invalid source should be checked and not be activated when starting libvirt daemon.