From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, kernel test robot <lkp@intel.com>,
        =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= <bjorn@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>
Subject: [PATCH 5.10 030/132] bpf, x86: Fix "no previous prototype" warning
Date:   Mon, 13 Dec 2021 10:29:31 +0100
Message-Id: <20211213092940.149571464@linuxfoundation.org>
In-Reply-To: <20211213092939.074326017@linuxfoundation.org>
References: <20211213092939.074326017@linuxfoundation.org>
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From: Björn Töpel <bjorn@kernel.org>

commit f45b2974cc0ae959a4c503a071e38a56bd64372f upstream.

The arch_prepare_bpf_dispatcher function does not have a prototype, and
yields the following warning when W=1 is enabled for the kernel build.

  >> arch/x86/net/bpf_jit_comp.c:2188:5: warning: no previous \
  prototype for 'arch_prepare_bpf_dispatcher' [-Wmissing-prototypes]
        2188 | int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, \
	int num_funcs)
             |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~

Remove the warning by adding a function declaration to include/linux/bpf.h.

Fixes: 75ccbef6369e ("bpf: Introduce BPF dispatcher")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211117125708.769168-1-bjorn@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/bpf.h |    1 +
 1 file changed, 1 insertion(+)

--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -666,6 +666,7 @@ int bpf_trampoline_unlink_prog(struct bp
 struct bpf_trampoline *bpf_trampoline_get(u64 key,
 					  struct bpf_attach_target_info *tgt_info);
 void bpf_trampoline_put(struct bpf_trampoline *tr);
+int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs);
 #define BPF_DISPATCHER_INIT(_name) {				\
 	.mutex = __MUTEX_INITIALIZER(_name.mutex),		\
 	.func = &_name##_func,					\