pahole currently only generates the btf_id for external function and
ftrace-able function. Some functions in the bpf_tcp_ca_kfunc_ids
are static (e.g. cubictcp_init). Thus, unless CONFIG_DYNAMIC_FTRACE
is set, btf_ids for those functions will not be generated and the
compilation fails during resolve_btfids.
This patch limits those functions to CONFIG_DYNAMIC_FTRACE. I will
address the pahole generation in a followup and then remove the
CONFIG_DYNAMIC_FTRACE limitation.
Fixes: e78aea8b2170 ("bpf: tcp: Put some tcp cong functions in allowlist for bpf-tcp-cc")
Reported-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Reported-by: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
Signed-off-by: Martin KaFai Lau <kafai@xxxxxx>
---
net/ipv4/bpf_tcp_ca.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/ipv4/bpf_tcp_ca.c b/net/ipv4/bpf_tcp_ca.c
index 6bb7b335ff9f..dff4f0eb96b0 100644
--- a/net/ipv4/bpf_tcp_ca.c
+++ b/net/ipv4/bpf_tcp_ca.c
@@ -185,6 +185,7 @@ BTF_ID(func, tcp_reno_cong_avoid)
BTF_ID(func, tcp_reno_undo_cwnd)
BTF_ID(func, tcp_slow_start)
BTF_ID(func, tcp_cong_avoid_ai)
+#ifdef CONFIG_DYNAMIC_FTRACE
#if IS_BUILTIN(CONFIG_TCP_CONG_CUBIC)
BTF_ID(func, cubictcp_init)
BTF_ID(func, cubictcp_recalc_ssthresh)
@@ -211,6 +212,7 @@ BTF_ID(func, bbr_ssthresh)
BTF_ID(func, bbr_min_tso_segs)
BTF_ID(func, bbr_set_state)
#endif
+#endif /* CONFIG_DYNAMIC_FTRACE */
BTF_SET_END(bpf_tcp_ca_kfunc_ids)
static bool bpf_tcp_ca_check_kfunc_call(u32 kfunc_btf_id)
--
2.30.2
