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> Linux kernel.  I cannot find any alternative license explaining the

> loadable kernel module exception which makes your position difficult

> to legally analyze.

>

> There is a note at the top of www.kernel.org/pub/linux/kernel/COPYING,

> but that states "user programs" which would clearly not apply to

> kernel modules.

>

> Could you clarify in writing what the exception precisely states?

 

Well, there really is no exception. However, copyright law obviously

hinges on the definition of "derived work", and as such anything can

always be argued on that point.

 

I personally consider anything a "derived work" that needs special hooks

in the kernel to function with Linux (ie it is _not_ acceptable to make a

small piece of GPL-code as a hook for the larger piece), as that obviously

implies that the bigger module needs "help" from the main kernel.

 

Similarly, I consider anything that has intimate knowledge about kernel

internals to be a derived work.

 

What is left in the gray area tends to be clearly separate modules: code

that had a life outside Linux from the beginning, and that do something

self-containted that doesn't really have any impact on the rest of the

kernel. A device driver that was originally written for something else,

and that doesn't need any but the standard UNIX read/write kind of

interfaces, for example.

 

> Issue #2

> ========

> I've found statements attributed to you that you think only 10% of

> the code in the current kernel was written by you.  By not being the

> sole copyright holder of the Linux kernel, a stated exception to

> the GPL seems invalid unless all kernel copyright holders agreed on

> this exception.  How does the exception cover GPL'd kernel code not

> written by you?  Has everyone contributing to the kernel forfeited

> their copyright to you or agreed with the exception?

 

Well, see above about the lack of exception, and about the fundamental

gray area in _any_ copyright issue. The "derived work" issue is obviously

a gray area, and I know lawyers don't like them. Crazy people (even

judges) have, as we know, claimed that even obvious spoofs of a work that

contain nothing of the original work itself, can be ruled to be "derived".

 

I don't hold views that extreme, but at the same time I do consider a

module written for Linux and using kernel infrastructures to get its work

done, even if not actually copying any existing Linux code, to be a