The safest method is to use kernels and modules with CONFIG_MODVERSIONS
configured, since the "interface" i.e. data types of parameters and
return value is encoded in the version string.
For "stable" symbols the version string won't change between kernel
versions, so insmod knows that it can safely ignore the actual
kernel version info in the module and load the module anyway, without
any "-f" option.
With the "-f" option you are telling the kernel that you know better
than what it does, and that you are taking full responsibility.
The maximum benefits of the CONFIG_MODVERSIONS option will be seen on
"stable" kernels, where the internals won't change as much as with
the development kernels. Since 2.0 will be out Real Soon Now,
you can check the validity of my arguments then, firsthand :-)
Cheers,
Bjorn <bj0rn@blox.se>