diff -Nru libvirt-1.3.1/debian/changelog libvirt-1.3.1/debian/changelog
--- libvirt-1.3.1/debian/changelog	2016-12-01 07:46:49.000000000 +0000
+++ libvirt-1.3.1/debian/changelog	2017-01-18 18:35:25.000000000 +0000
@@ -1,3 +1,11 @@
+libvirt (1.3.1-1ubuntu10.7) xenial; urgency=medium
+
+  [ Mauricio Faria de Oliveira ]
+  * Use a fixed uid/gid for libvirt-qemu user to avoid permission
+    issues on network filesystems like NFS (backport) (LP: #1637601).
+
+ -- Christian Ehrhardt <christian.ehrhardt@canonical.com>  Wed, 18 Jan 2017 16:15:34 +0100
+
 libvirt (1.3.1-1ubuntu10.6) xenial; urgency=medium
 
   * d/apparmor/usr.lib.libvirt.virt-aa-helper: add missing rules for name
diff -Nru libvirt-1.3.1/debian/libvirt-bin.NEWS libvirt-1.3.1/debian/libvirt-bin.NEWS
--- libvirt-1.3.1/debian/libvirt-bin.NEWS	2016-12-01 07:46:49.000000000 +0000
+++ libvirt-1.3.1/debian/libvirt-bin.NEWS	2017-01-18 15:15:19.000000000 +0000
@@ -1,3 +1,25 @@
+libvirt (1.3.1-1ubuntu10.7) unstable; urgency=medium
+
+  libvirt-daemon-system now uses the allocated uid and gid 64055
+  for the libvirt-qemu user and group on new installations, when
+  the uid/gid is available (Xenial: debconf warning isn't shown).
+
+  On existing installations, which have different uid/gid values
+  assigned, the recommended procedure is to reassign the uid/gid
+  (might require considerations for ownership/permission changes).
+  No debconf warning is shown in this case; only this NEWS entry.
+
+  This change is in order to prevent I/O errors during migration
+  of guests with disk image files shared over NFS, caused by the
+  different uid/gid ownership between the source and destination
+  host systems, which leads to access/permission errors with NFS.
+
+  If guest migration over NFS is not a requirement in the system,
+  there should not be any impact to the guests for not using the
+  allocated uid/gid.
+
+ -- Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>  Thu, 18 Nov 2016 13:56:38 -0200
+
 libvirt (1.2.9~rc1-1) experimental; urgency=medium
 
   libvirtd now uses PolicyKit instead of unix socket domain permissions for r/w
diff -Nru libvirt-1.3.1/debian/libvirt-bin.postinst libvirt-1.3.1/debian/libvirt-bin.postinst
--- libvirt-1.3.1/debian/libvirt-bin.postinst	2016-12-01 07:46:49.000000000 +0000
+++ libvirt-1.3.1/debian/libvirt-bin.postinst	2017-01-18 15:14:34.000000000 +0000
@@ -17,6 +17,10 @@
 # for details, see http://www.debian.org/doc/debian-policy/ or
 # the debian-policy package
 
+# Allocated UID and GID for libvirt-qemu
+LIBVIRT_QEMU_UID=64055
+LIBVIRT_QEMU_GID=64055 # not used in Xenial.
+
 add_users_groups()
 {
     if ! getent group libvirtd >/dev/null; then
@@ -39,6 +43,13 @@
         addgroup --quiet --system kvm
     fi
     if ! getent passwd libvirt-qemu >/dev/null; then
+
+        # set uid if available (expected); don't fail otherwise.
+        PARAMETER_UID=''
+        if ! getent passwd $LIBVIRT_QEMU_UID >/dev/null; then
+            PARAMETER_UID="--uid $LIBVIRT_QEMU_UID"
+        fi
+
         adduser --quiet \
             --system \
             --ingroup kvm \
@@ -48,6 +59,7 @@
             --home /var/lib/libvirt \
             --no-create-home \
             -gecos "Libvirt Qemu" \
+            $PARAMETER_UID \
             libvirt-qemu
     fi
     if ! getent passwd libvirt-dnsmasq >/dev/null; then