Re: [PATCH 5/6] net: Change CONFIG_INET to CONFIG_LEGACY_IP for IPv4-only code

> diff --git a/net/core/filter.c b/net/core/filter.c
> index ad71ceefcb5e..ef99bd9fddd6 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c

[ ... ]

> @@ -6095,7 +6095,7 @@ static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu)
>  }
>  #endif
>
> -#if IS_ENABLED(CONFIG_INET)
> +#if IS_ENABLED(CONFIG_LEGACY_IP)
>  static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
>  			       u32 flags, bool check_mtu)

bpf_fib_set_fwd_params() above this hunk is still guarded by
CONFIG_INET, and its only two callers are bpf_ipv4_fib_lookup()
(now CONFIG_LEGACY_IP) and bpf_ipv6_fib_lookup() (CONFIG_IPV6).

When CONFIG_INET=y with both CONFIG_LEGACY_IP=n and CONFIG_IPV6=n,
bpf_fib_set_fwd_params() becomes an unused static function, which
will produce a -Wunused-function warning and break CONFIG_WERROR
builds.

Should the guard on bpf_fib_set_fwd_params() be changed to
something like:

  #if IS_ENABLED(CONFIG_LEGACY_IP) || IS_ENABLED(CONFIG_IPV6)

to match its actual callers?


---
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CI run summary: https://github.com/kernel-patches/bpf/actions/runs/23838411859