Hi, Richard: 
       there don't have  SELinux  problem . 
[root@gz-op-vmhost01 ~]# getenforce
[root@gz-op-vmhost01 ~]# ll /var/tmp/ -a
total 28
drwxrwxrwt  7 root root 4096 Jan 10 15:17 .
drwxr-xr-x 21 root root 4096 Jun 10  2019 ..
drwxr-xr-x  2 abrt abrt 4096 Nov 23  2017 abrt
drwxr-xr-x  3 root root 4096 Jan 10 15:17 .guestfs-0

      someone suggest me run  yum upgrade   ,this make a lot of software upgraded .   then the problem sloved, but don't get  the reason . 

------------------ 原始邮件 ------------------
发件人: "Richard W.M. Jones"<rjones@redhat.com>;
发送时间: 2020年1月9日(星期四) 晚上9:44
收件人: "谢威"<249016681@qq.com>;
抄送: "Tomáš Golembiovský"<tgolembi@redhat.com>;"libguestfs"<libguestfs@redhat.com>;
主题: Re: [Libguestfs] 回复: bug report

On Wed, Jan 08, 2020 at 09:05:55PM +0800, 谢威 wrote:
> &gt; libguestfs: trace: disk_create "/tmp/libguestfsHRQGUn/overlay1.qcow2" "qcow2" -1 "backingfile:/var/tmp/.guestfs-0/appliance.d/root" "backingformat:raw"
> &gt; libguestfs: command: run: qemu-img
> &gt; libguestfs: command: run: \ create
> &gt; libguestfs: command: run: \ -f qcow2
> &gt; libguestfs: command: run: \ -o backing_file=/var/tmp/.guestfs-0/appliance.d/root,backing_fmt=raw
> &gt; libguestfs: command: run: \ /tmp/libguestfsHRQGUn/overlay1.qcow2
> &gt; qemu-img: /tmp/libguestfsHRQGUn/overlay1.qcow2: A regular file was expected by the 'file' driver, but something else was given
> &gt; Could not open backing image to determine size.

There's something really weird going on here with your system.
Could it be that /var/tmp is not readable?

Tomas already suggested doing this:

  rm -rf /var/tmp/.guestfs-*

then try to run libguestfs-test-tool again.  If it still doesn't work,
have a look at the permissions of files in /var/tmp/.guestfs-0 or if
you see any SELinux audit messages.


Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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