From c9b30877a03c432ca6925dbe66563a8147773fd2 Mon Sep 17 00:00:00 2001 From: Alan Maguire Date: Fri, 12 Jul 2024 10:28:59 +0100 Subject: [PATCH] bpf: Eliminate remaining "make W=1" warnings in kernel/bpf/btf.o MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 2454075f8e2915cebbe52a1195631bc7efe2b7e1 ] As reported by Mirsad [1] we still see format warnings in kernel/bpf/btf.o at W=1 warning level: CC kernel/bpf/btf.o ./kernel/bpf/btf.c: In function ‘btf_type_seq_show_flags’: ./kernel/bpf/btf.c:7553:21: warning: assignment left-hand side might be a candidate for a format attribute [-Wsuggest-attribute=format] 7553 | sseq.showfn = btf_seq_show; | ^ ./kernel/bpf/btf.c: In function ‘btf_type_snprintf_show’: ./kernel/bpf/btf.c:7604:31: warning: assignment left-hand side might be a candidate for a format attribute [-Wsuggest-attribute=format] 7604 | ssnprintf.show.showfn = btf_snprintf_show; | ^ Combined with CONFIG_WERROR=y these can halt the build. The fix (annotating the structure field with __printf()) suggested by Mirsad resolves these. Apologies I missed this last time. No other W=1 warnings were observed in kernel/bpf after this fix. [1] https://lore.kernel.org/bpf/92c9d047-f058-400c-9c7d-81d4dc1ef71b@gmail.com/ Fixes: b3470da314fd ("bpf: annotate BTF show functions with __printf") Reported-by: Mirsad Todorovac Suggested-by: Mirsad Todorovac Signed-off-by: Alan Maguire Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20240712092859.1390960-1-alan.maguire@oracle.com Signed-off-by: Sasha Levin --- kernel/bpf/btf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 0c9d93e2c18f..d3eb75bfd971 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -349,7 +349,7 @@ const char *btf_type_str(const struct btf_type *t) struct btf_show { u64 flags; void *target; /* target of show operation (seq file, buffer) */ - void (*showfn)(struct btf_show *show, const char *fmt, va_list args); + __printf(2, 0) void (*showfn)(struct btf_show *show, const char *fmt, va_list args); const struct btf *btf; /* below are used during iteration */ struct {