cannot access storage file (as uid:107, gid:107)permission denied

今日はspice-protocol spice-gtk spice qemuを自分でコンパイルし、virshで虚機を作成したいと思っています.
# virsh define demo.xml
ドメインdemoの定義(demo.xmlから)
# virsh start demo
    cannot access storage file (as uid:107, gid:107)  permission denied
解決方法:
     
Changing  /etc/libvirt/qemu.conf  make working things. Uncomment user/group to work as  root .

# The user for QEMU processes run by the system instance. It can be
# specified as a user name or as a user id. The qemu driver will try to
# parse this value first as a name and then, if the name doesn't exist,
# as a user id.
#
# Since a sequence of digits is a valid user name, a leading plus sign
# can be used to ensure that a user id will not be interpreted as a user
# name.
#
# Some examples of valid values are:
#
#       user = "qemu"   # A user named "qemu"
#       user = "+0"     # Super user (uid=0)
#       user = "100"    # A user named "100" or a user with uid=100
#
user = "root"

# The group for QEMU processes run by the system instance. It can be
# specified in a similar way to user.
group = "root"

# Whether libvirt should dynamically change file ownership
# to match the configured user/group above. Defaults to 1.
# Set to 0 to disable file ownership changes.
#dynamic_ownership = 1