bpf_stream_vprintk_impl() is using printf() type of format, and compiler is not happy about them as is: kernel/bpf/stream.c:241:9: error: function ‘bpf_stream_vprintk_impl’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] 241 | ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt__str, data.bin_args); | ^~~ Fix the compilation errors by adding __printf() attribute. Fixes: 5ab154f1463a ("bpf: Introduce BPF standard streams") Signed-off-by: Andy Shevchenko --- kernel/bpf/stream.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/bpf/stream.c b/kernel/bpf/stream.c index 0b6bc3f30335..4bff72e3c16f 100644 --- a/kernel/bpf/stream.c +++ b/kernel/bpf/stream.c @@ -212,6 +212,7 @@ __bpf_kfunc_start_defs(); * Avoid using enum bpf_stream_id so that kfunc users don't have to pull in the * enum in headers. */ +__printf(2, 0) __bpf_kfunc int bpf_stream_vprintk_impl(int stream_id, const char *fmt__str, const void *args, u32 len__sz, void *aux__prog) { -- 2.50.1