[libvirt-users] command guest-file-open failed to open file - Permission denied

hello, I am using libvirt 1.2.17 on CentOS 7.2 - kernel 3.10.0-327.13.1.el7.x86_64. The command guest-file-open failed to open file with error "Permission denied", the detail is as below: virsh qemu-agent-command instance-00000a9c '{"execute":"guest-file-open", "arguments":{"path":"/home/centos/test","mode":"r"}}' error: internal error: unable to execute QEMU agent command 'guest-file-open': failed to open file '/home/centos/test' (mode: 'r'): Permission denied In the guest, the file '/home/centos/test' exist and the access permissions is 777 as below: -rwxrwxrwx. 1 centos centos 18 Oct 27 11:16 test How can I fix it? Thanks very much!!! -mkliu28