Confirmed kernel from -proposed fixes the issue. Test case program and vsftpd both run without triggering the kernel messages.
[ 0.000000] Linux version 3.13.0-30-generic (buildd@allspice) (gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1) ) #54-Ubuntu SMP Mon Jun 9 22:45:01 UTC 2014 (Ubuntu 3.13.0-30.54-generic 3.13.11.2) [ 0.000000] Booting paravirtualized kernel on Xen [ 0.000000] Xen version: 4.4.0 (preserve-AD)
Confirmed kernel from -proposed fixes the issue. Test case program and vsftpd both run without triggering the kernel messages.
[ 0.000000] Linux version 3.13.0-30-generic (buildd@allspice) (gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1) ) #54-Ubuntu SMP Mon Jun 9 22:45:01 UTC 2014 (Ubuntu 3.13.0- 30.54-generic 3.13.11.2)
[ 0.000000] Booting paravirtualized kernel on Xen
[ 0.000000] Xen version: 4.4.0 (preserve-AD)