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/[email protected]/

Fixes: 31d0bc81637d ("bpf: Move to generic BTF show support, apply it to seq files/strings")
Reported-by: Mirsad Todorovac <[email protected]>
Signed-off-by: Alan Maguire <[email protected]>
Tested-by: Mirsad Todorovac <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

1 files changed, 4 insertions, 4 deletions

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 4ff11779699e..d5019c4454d6 100644
--- 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;