editing the file when mount the file system using 9pfs. it will report fsync failed. 

 I have get a fsync error when I use the 9pfs on the kvm guest. it appears when I use vi editor and sysbench. I have not  found the reason yet. can you tell something about it?  the attache is the picture. and there is no any log which I can provide.

 My qemu version is qemu-kvm-0.13.0, and my  host  linux distributions is 2.6.32-431.el6.x86_64 and the guest vm is the same version which enable 9pfs and 9pnet support. I use the string of "mount -t 9p -o trans=virtio test_mount /tmp/shared/ -oversion=9p2000.L,posixacl" to get the file system.