Re: MODULE_LICENSE and EXPORT_SYMBOL_GPL

Roy Murphy
2001-10-19T17:03:42Z

'Twas brillig when Taral scrobe:
>You're quite right. Module insertion is linking. And distributing a
>kernel with binary-only modules already inserted would be a GPL
>violation. What modules do is let people do the link at the last stage
>-- the end user. The GPL does not restrict what end-users do with your
>code if it doesn't involve redistribution.

The point was made earlier that a module might include some code expanded from
a macro in a kernel header file. Producers of binary
modules could adopt a "clean room" approach (as the first cloners of
the IBM PC BIOS did) and have one group write a technical specification
for any necessary kernel headers and have a second group implement
substitute headers from the specification.

>I also think this is somewhat ridiculous. If I (the binary module
>maker) distribute a program which effectively replicates the
>functionality of insmod without the licence checking, and distribute
>that program with my module, am I violating any restrictions? I don't
>think so, since it's the end-user that ends up linking the kernel to
>the module. No linked products are actually distributed...

In the US it may be a violation of the DCMA prohibition on
circumvention of "effective access controls" (and perhaps violations of
corresponding laws in some European countries). Though that's a whole
'nother huge legal morass.