On Sat, Jun 28, 2014 at 12:26:14AM -0700, Alexei Starovoitov wrote: > On Fri, Jun 27, 2014 at 11:28 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: > > On Fri, Jun 27, 2014 at 11:12 PM, Alexei Starovoitov <ast@xxxxxxxxxxxx> wrote: > > If you want to add GPL-only functions in the future, that would be one > > thing. But if someone writes a nice eBPF compiler, and someone else > > writes a little program that filters on network packets, I see no > > reason to claim that the little program is a derivative work of the > > kernel and therefore must be GPL. > > I think we have to draw a line somewhere. Say, tomorrow I want > to modify libpcap to emit eBPF based on existing tcpdump syntax. > Would it mean that tcpdump filter strings are GPLed? Definitely not, > since they existed before and can function without new libpcap. > But if I write a new packet filtering program in C, compile it > using LLVM->eBPF and call into in-kernel helper functions > (like bpf_map_lookup_elem()), I think it's exactly the derivative work. > It's analogous to kernel modules. If module wants to call > export_symbol_gpl() functions, it needs to be GPLed. Here all helper > functions are GPL. So we just have a blank check for eBPF program. I agree, these eBFP programs should be GPL-compatible licensed as well. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
