I actually tried this to see what would happen. First I created an overlay so as not to modify the original guest: $ rm -f overlay.qcow2 $ qemu-img create -f qcow2 -o backing_file=F16x64.img overlay.qcow2 Here is the original file permissions and SELinux context: $ guestfish --ro -a overlay.qcow2 -i llz /etc/shadow ----------. root root system_u:object_r:shadow_t:s0 /sysroot/etc/shadow After editing with guestmount + vi there was no change so it appears to work correctly: $ guestfish --ro -a overlay.qcow2 -i llz /etc/shadow ----------. root root system_u:object_r:shadow_t:s0 /sysroot/etc/shadow I also tried guestmount + emacs. emacs refused to save the file, complaining: Doing lsetfilecon: operation not supported, /tmp/mnt/etc/shadow This even failed when I used 'guestmount --selinux' option, so I have filed a bug: https://bugzilla.redhat.com/show_bug.cgi?id=814933 For completeness I tried virt-edit: $ virt-edit -a overlay.qcow2 /etc/shadow $ guestfish --ro -a overlay.qcow2 -i llz /etc/shadow ----------. root root system_u:object_r:shadow_t:s0 /sysroot/etc/shadow and guestfish 'edit': $ guestfish -a overlay.qcow2 -i emacs /etc/shadow $ guestfish --ro -a overlay.qcow2 -i llz /etc/shadow ----------. root root system_u:object_r:shadow_t:s0 /sysroot/etc/shadow and as you can see both work correctly. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones New in Fedora 11: Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 70 libraries supprt'd http://fedoraproject.org/wiki/MinGW http://www.annexia.org/fedora_mingw