在Fedo8中使用xen安装guest OS的问题

fancy198189

我在使用virt-manager时,选择用映像文件的方式来安装guestOS。但是才开始就遇到了下面的问题，导致安装终止。请问这是什么意思，有什么解决方法？
弹出窗口报警如下：
Unable to complete install: 'virDomainCreateLinux() failed POST操作失败: (xend.err 'Device 51712 (vbd) could not be connected.\nFile /xen/Fedo/fedo8.img is loopback-mounted through /dev/loop0,\nwhich is mounted in the privileged domain,\nand so cannot be mounted by a guest.')'
点击detail时，具体信息如下：
Unable to complete install ' virDomainCreateLinux() failed POST操作失败: (xend.err 'Device 51712 (vbd) could not be connected.\nFile /xen/Fedo/fedo8.img is loopback-mounted through /dev/loop0,\nwhich is mounted in the privileged domain,\nand so cannot be mounted by a guest.')
Traceback (most recent call last):
File "/usr/share/virt-manager/virtManager/create.py", line 616, in do_install
dom = guest.start_install(False, meter = meter)
File "/usr/lib/python2.5/site-packages/virtinst/Guest.py", line 724, in start_install
return self._do_install(consolecb, meter)
File "/usr/lib/python2.5/site-packages/virtinst/Guest.py", line 741, in _do_install
self.domain = self.conn.createLinux(install_xml, 0)
File "/usr/lib/python2.5/site-packages/libvirt.py", line 573, in createLinux
if ret is None:raise libvirtError('virDomainCreateLinux() failed', conn=self)
libvirtError: virDomainCreateLinux() failed POST操作失败: (xend.err 'Device 51712 (vbd) could not be connected.\nFile /xen/Fedo/fedo8.img is loopback-mounted through /dev/loop0,\nwhich is mounted in the privileged domain,\nand so cannot be mounted by a guest.')
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