64bit ext4 and kernel version compatibility

[R. Ramesh]

Hi,

  On my DVR, I am running fairly old version of kernel 
(3.13.0-132-generic, mythbuntu 14.04.5 LTS). I want to convert ext4 fs 
on this server to 64bit so that I can grow it past 16TB limit. At that 
time of installation (2014), e2fsprogs did not support 64bit fs.  Now it 
does. Before I get the source and build and update e2fsprogs and then 
the file system, I want to make sure that my current kernel version does 
not have any limitation to support 64bit ext4.   My google searches do 
not mention any kernel limitations. I think this is due to my inability 
to ask the right question to google. Appreciate any help I can get on 
answering my question.

At this time it is difficult for me to upgrade the kernel without 
updating the distribution (and hence mythtv) and that path is beyond me 
at this time due to time constraints.

Ramesh