On Tuesday 21 December 2010 03:17:40 Piotr Gluszenia Slawinski wrote:
On Mon, 20 Dec 2010, Alan Cox wrote:
My point which people keep missing is that graphics stacks are a single entity, that span kernel and userspace, one cannot exist without the other, and there are interfaces that join them.
As a copyright holder on the kernel I'll also remind the people concerned that the definition of a derivative work is a legal not a technical one and if the kernel and user space cannot be used except together and one half depends on GPL elements I hope your lawyers have reviewed it carefully. I have never given anyone permission to link my GPL kernel contributions with anything but GPL code, modular or otherwise, except according to the derivative work rules laid down by the GPL (and indeed by the boundaries placed on copyright law).
but it can be circumvented by writing GPL driver which will act as 'glue logic' inbetween userspace driver and which will work in kernel space?
technically then driver would be GPL, except it's closed parts which will be ran in userspace... or can you forbid usage of certain closed userspace components with kernel?
Anyone can try shipping this and risk a lawsuit, and all copyright holders of the kernel can try suing people that distribute such code. Most sensible people stay out of both the shipping questionable code and the suing part, but apparently the entire mobile phone industry is already doing both, so we can just wait and see if anyone has deep enough pockets to bring this up in court first ;-).
The only thing that is currently being enforced is that no interfaces enter the mainline kernel that rely on closed source user space. Once something is merged in mainline, you are generally free to write code under any license you want against that interface.
Arnd