Possibility for a different permissive license?

[falhumai96]

Hello,

I noticed that QEMU released the TCG component under a more permissive license (BSD license): https://wiki.qemu.org/License. In addition, the CPU component, say i386, sources have GNU Lesser General Public License in the top of the source files, e.g.: https://github.com/qemu/qemu/blob/master/target/i386/tcg/translate.c.

Can you guys perhaps release the project under a more permissive license? This is a great a project, but it would be a sham not to be able to use it with other projects unless we convert our projects into GPLv2 as well. Perhaps there could be a discussion between you guys and QEMU devs about whether or not Unicorn can use the CPU component of QEMU permissively so that there won't be a tight coupling with GPLv2?

[wtdcode]

I (and probably we, the unicorn engine team) am not a license expert and if you wish a license change, I suggest you pushing the discussion.

[berrange]

Closing the loop, the following email was sent to QEMU maintainers

https://lists.nongnu.org/archive/html/qemu-devel/2025-02/msg03975.html

Per my own response to that mail, I don't think the licensing situation is as simple as it is made out in this ticket. While some parts of QEMU are under a permissive license, those parts still consume other APIs from the QEMU codebase that are under the GPL-v2-or-later and/or GPL-v2-only. So when selecting any non-trivial subset of QEMU code, the combined work of will usually become GPL-v2-only. I don't see this situation significantly changing in future on the QEMU side.

[wtdcode]

Closing the loop, the following email was sent to QEMU maintainers

https://lists.nongnu.org/archive/html/qemu-devel/2025-02/msg03975.html

Per my own response to that mail, I don't think the licensing situation is as simple as it is made out in this ticket. While some parts of QEMU are under a permissive license, those parts still consume other APIs from the QEMU codebase that are under the GPL-v2-or-later and/or GPL-v2-only. So when selecting any non-trivial subset of QEMU code, the combined work of will usually become GPL-v2-only. I don't see this situation significantly changing in future on the QEMU side.

Thanks for the clarification!