2026-03-10, 20:58:15 +0100, Arnd Bergmann wrote: > On Tue, Mar 10, 2026, at 20:40, Kolbjørn Barmen wrote: > > On Mon, 9 Mar 2026, Krzysztof Kozlowski wrote: > >> On 09/03/2026 03:19, Fernando Fernandez Mancera wrote: > >> > >> It must stay module for me. Alternatively, drop it, but then some users > >> will be really affected. > > > > I agree. If anything I would prefer to see IPv4 be made optional (and > > modular) as well, and not as something IPv6 depends on, it's (AFAIK) > > impossible today to build an IPv6-only Linux kernel. > [...] > For optional IPv4 support, I would expect that it's possible > to make it a loadable module, with a significant amount of > work and little benefit. Loading an ipv6 module without also > loading ipv4 sounds completely unrealistic though, given > the way the code is structured today.
I played with building IPv6-only kernels some years ago. It was possible (at least for the reduced config I was using as a start), but yes, a fair amount of investigation and churn, to find all the IPv4 common code and turn it into "generic" common code. IPv4 as a module would get us in the same mess with have with IPv6, let's not do that. But even IPV4=n, I abandonned the idea because of the work/churn vs benefit ratio. -- Sabrina
