unable to load modules with CONFIG_MODVERSIONS=y after commit 8ab2ae655b

[Jan Stancek]

Hi,

Starting with 4.9-rc8 / commit 8ab2ae655b ("default exported asm symbols to 
zero")
I'm running into issue with kernel built with CONFIG_MODVERSIONS=y
and (older) binutils (binutils-2.25.1-20.base.el7.ppc64le). 

Modules fail to load, for example:

[    3.163646] Found checksum 0 vs module 4829A47E 
[    3.163787] dm_mod: disagrees about version of symbol memcpy 
[    3.163862] dm_mod: Unknown symbol memcpy (err -22)

Bisect led me to 8ab2ae655b, reverting it allows boot to
progress as before.

Regards,
Jan