Re: [PATCH v2 bpf-next] bpf: cgroup: Fix build error without CONFIG_NET

[Yonghong Song]

On 7/3/19 1:26 AM, YueHaibing wrote:
> If CONFIG_NET is not set and CONFIG_CGROUP_BPF=y,
> gcc building fails:
> 
> kernel/bpf/cgroup.o: In function `cg_sockopt_func_proto':
> cgroup.c:(.text+0x237e): undefined reference to `bpf_sk_storage_get_proto'
> cgroup.c:(.text+0x2394): undefined reference to `bpf_sk_storage_delete_proto'
> kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_getsockopt':
> (.text+0x2a1f): undefined reference to `lock_sock_nested'
> (.text+0x2ca2): undefined reference to `release_sock'
> kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_setsockopt':
> (.text+0x3006): undefined reference to `lock_sock_nested'
> (.text+0x32bb): undefined reference to `release_sock'
> 
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Suggested-by: Stanislav Fomichev <sdf@xxxxxxxxxxx>
> Fixes: 0d01da6afc54 ("bpf: implement getsockopt and setsockopt hooks")
> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>

Acked-by: Yonghong Song <yhs@xxxxxx>

> ---
> v2: use ifdef macro
> ---
>   kernel/bpf/cgroup.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
> index 76fa007..0a00eac 100644
> --- a/kernel/bpf/cgroup.c
> +++ b/kernel/bpf/cgroup.c
> @@ -939,6 +939,7 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
>   }
>   EXPORT_SYMBOL(__cgroup_bpf_run_filter_sysctl);
>   
> +#ifdef CONFIG_NET
>   static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
>   					     enum bpf_attach_type attach_type)
>   {
> @@ -1120,6 +1121,7 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
>   	return ret;
>   }
>   EXPORT_SYMBOL(__cgroup_bpf_run_filter_getsockopt);
> +#endif
>   
>   static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,
>   			      size_t *lenp)
> @@ -1386,10 +1388,12 @@ static const struct bpf_func_proto *
>   cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
>   {
>   	switch (func_id) {
> +#ifdef CONFIG_NET
>   	case BPF_FUNC_sk_storage_get:
>   		return &bpf_sk_storage_get_proto;
>   	case BPF_FUNC_sk_storage_delete:
>   		return &bpf_sk_storage_delete_proto;
> +#endif
>   #ifdef CONFIG_INET
>   	case BPF_FUNC_tcp_sock:
>   		return &bpf_tcp_sock_proto;
>