It turned out to be an apparmor issue. As I was having my mysql data in a different location during update ls -la /etc/apparmor.d/usr.sbin.mysqld was overwrriten. This resulted in error. after correcting that file every thing is back to normal.
It turned out to be an apparmor issue. As I was having my mysql data in a different location during update ls -la /etc/apparmor. d/usr.sbin. mysqld was overwrriten. This resulted in error. after correcting that file every thing is back to normal.