License issues roil Linux developer community
- By Joab Jackson
- Jun 15, 2007
Should the Linux kernel be licensed under the new version of the Gnu General Public License, or should it stick with the old version? The question has sparked a heated debate on the mailing list
for Linux kernel developers. Hundreds of messages have zapped back and forth across the list debating the merits of the new open-source license, now in the final stages of preparation by the Free Software Foundation.
The copyright owner of the Linux kernel, Linus Torvalds, has stated that he would prefer to stick with the previous version of the kernel, Version 2. His chief lieutenants, Alan Cox and Andrew Morton, have sided with Torvalds. "I still think GPLv2 is simply the better license," Torvalds wrote.
Complicating the picture is that fact that Torvalds has said that if Sun Microsystems moves its open-source Solaris operating system ' another version of Unix ' he'd consider dual-licensing Linux so that the two projects could share code
. "If we can avoid having two kernels with two different licenses and the friction that causes, I at least see the reason for GPLv3," he wrote.
Whether he could find agreement with the many coders who help write the Linux kernel is another matter.
At heart of the issue are changes in the license
, which was last updated 15 years ago. Many developers see problems with the new license. The older version, GPLv2, paved the way for open development of the Linux kernel. It stipulated that any code publicly available that was under the GPL was free for use by others ' but if the modified version of that software was publicly used or sold as a product, any modifications of that software had to be made available as well, as source code.
In this way, software under the GPL could incorporate the subsequent changes made downstream if they proved to be beneficial. Torvalds noted that Linux development has been successful thanks to this open nature of GPLv2. "From the very beginning of Linux, even before I chose the GPLv2 as the license, the thing I cared about was that source code be freely available," he wrote. "I didn't want money, I didn't want hardware. I just wanted the improvements back."
Overseen by Richard Stallman, Version 3 of the GPL
contains some pretty radical changes
' and pushes the definition of free software into a controversial realm. For one thing, GPLv3 forbids the software to be used in deals such as the one that Novell cut with Microsoft last year. Under that deal, Microsoft would distribute to its customers vouchers for discounted copies of Novell Suse, a Linux distribution. Under GPLv3, third parties cannot distribute the software in a way that allows recipients not to abide by the condition of mandatory sharing of code.
Most developers took issue with how GPLv3 guarded against what is known as Tivoization, after the popular Tivo digital video recorder that uses Linux as its operating system. Tivo configures its units in such a way that modified copies of the software could not run on the hardware. Tivo did this in order to ensure that the units could not be tampered with to illegally copy content, which modified software could conceivably be written to do.
For many developers who actually worked on the code, this seemed to be a bitter pill, and they were happy that GPLv3 explicitly forbids this practice. Dave Neuer wrote about his dissatisfaction with the idea of a hardware vendor being able to lock him out of the use of a box he had purchased "if [that company] benefited from code which was intended to be modifiable by end users."
More than a few developers, though, felt that the license was, in the words of one contributor "forcing ethics and morals" on users.
Even developers who were partial to GPLv3 admitted that moving the Linux code base to the new license would be problematic. Since many people have contributed to the code, everyone's approval would be needed in order to move the Linux kernel to the new license, which would be a demanding and ' some argued ' futile task.
"There are a lot of lost or dead maintainers ' which makes it impossible to get all the maintainers' permission," Tarkan Erimer wrote.
Joab Jackson is the senior technology editor for Government Computer News.