double free issue, mvpp2 driver, armada375 modules

Hello,

enclosed the kernel panic we obtain after boot with a slightly patched 
upstream kernel (4.5.2).

(as well as the patchset applied to the upstream kernel, so that you can 
know which code we are talking about. Too bad we cannot use the upstream 
kernel but we had no choice about this + we're no experts so we rely on 
provided patches, adapted to our bootloader and hardware for this)

Reproduce:
boot on kernel on an armada375 module, connect to it, launch a top in 
commandline

As seen with Marcin Wojtas, reverting commit 
e864b4c7b184bde36fa6a02bb3190983d2f796f9 fixes this issue.

Reporting upstream so that you can decide what should be done next

Tell me if you need more information

Regards

Raphael