Comment 6 for bug 201799

Alternative solution:

1. Edit /etc/apparmor.d/usr.sbin.mysqld and add the following two lines:

    /home/mysql/ r,
    /home/mysql/** rwk,

    somewhere in the middle of the file. After the /var/lib/mysql lines would be fine.
2. /etc/init.d/apparmor restart
3. /etc/init.d/mysql restart

You retain the benefis of apparmor. Maybe the comments in /etc/mysql/my.cnf regarding apparmor can be expanded to cover exactly what you should do if you reset mysql_data.