bpf: annotate BTF show functions with __printf

-Werror=suggest-attribute=format warns about two functions
in kernel/bpf/btf.c [1]; add __printf() annotations to silence
these warnings since for CONFIG_WERROR=y they will trigger
build failures.

[1] https://lore.kernel.org/bpf/a8b20c72-6631-4404-9e1f-0410642d7d20@gmail.com/

Fixes: 31d0bc81637d ("bpf: Move to generic BTF show support, apply it to seq files/strings")
Reported-by: Mirsad Todorovac <mtodorovac69@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Mirsad Todorovac <mtodorovac69@yahoo.com>
Link: https://lore.kernel.org/r/20240711182321.963667-1-alan.maguire@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 4ff11779699ef34fee42ab3a1d0a98f57a11116b..d5019c4454d64fac59c301c65d88b64f27d43d46 100644 (file)
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -7538,8 +7538,8 @@ static void btf_type_show(const struct btf *btf, u32 type_id, void *obj,
        btf_type_ops(t)->show(btf, t, type_id, obj, 0, show);
 }
 
-static void btf_seq_show(struct btf_show *show, const char *fmt,
-                        va_list args)
+__printf(2, 0) static void btf_seq_show(struct btf_show *show, const char *fmt,
+                                       va_list args)
 {
        seq_vprintf((struct seq_file *)show->target, fmt, args);
 }
@@ -7572,8 +7572,8 @@ struct btf_show_snprintf {
        int len;                /* length we would have written */
 };
 
-static void btf_snprintf_show(struct btf_show *show, const char *fmt,
-                             va_list args)
+__printf(2, 0) static void btf_snprintf_show(struct btf_show *show, const char *fmt,
+                                            va_list args)
 {
        struct btf_show_snprintf *ssnprintf = (struct btf_show_snprintf *)show;
        int len;