Re: [linux-stable-rc:queue/6.0 311/314] include/linux/bpf.h:2310:20: error: static declaration of 'bpf_prog_inc_misses_counter' follows non-static declaration

[Jiri Olsa <olsajiri@gmail.com>]

On Wed, Nov 23, 2022 at 10:15:29PM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git queue/6.0
> head:   18012ab4ede3cad45033b4403c744a54d0b81438
> commit: 618ec81a64fe23571a79b77c26b5d326425934f8 [311/314] bpf: Prevent bpf program recursion for raw tracepoint probes
> config: microblaze-randconfig-r032-20221120
> compiler: microblaze-linux-gcc (GCC) 12.1.0
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git/commit/?id=618ec81a64fe23571a79b77c26b5d326425934f8
>         git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
>         git fetch --no-tags linux-stable-rc queue/6.0
>         git checkout 618ec81a64fe23571a79b77c26b5d326425934f8
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=microblaze SHELL=/bin/bash kernel/bpf/
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from tools/lib/bpf/relo_core.c:5:
> >> include/linux/bpf.h:2310:20: error: static declaration of 'bpf_prog_inc_misses_counter' follows non-static declaration
>     2310 | static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>          |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    include/linux/bpf.h:1970:14: note: previous declaration of 'bpf_prog_inc_misses_counter' with type 'void(struct bpf_prog *)'
>     1970 | void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog);
>          |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> --
>    In file included from kernel/bpf/syscall.c:4:
> >> include/linux/bpf.h:2310:20: error: static declaration of 'bpf_prog_inc_misses_counter' follows non-static declaration
>     2310 | static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>          |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    include/linux/bpf.h:1970:14: note: previous declaration of 'bpf_prog_inc_misses_counter' with type 'void(struct bpf_prog *)'
>     1970 | void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog);
>          |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> >> kernel/bpf/syscall.c:2097:14: error: redefinition of 'bpf_prog_inc_misses_counter'
>     2097 | void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>          |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    include/linux/bpf.h:2310:20: note: previous definition of 'bpf_prog_inc_misses_counter' with type 'void(struct bpf_prog *)'
>     2310 | static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>          |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> --
>    In file included from include/linux/bpf_verifier.h:7,
>                     from kernel/bpf/btf.c:19:
> >> include/linux/bpf.h:2310:20: error: static declaration of 'bpf_prog_inc_misses_counter' follows non-static declaration
>     2310 | static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>          |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    include/linux/bpf.h:1970:14: note: previous declaration of 'bpf_prog_inc_misses_counter' with type 'void(struct bpf_prog *)'
>     1970 | void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog);
>          |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>    kernel/bpf/btf.c: In function 'btf_seq_show':
>    kernel/bpf/btf.c:6609:29: warning: function 'btf_seq_show' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
>     6609 |         seq_vprintf((struct seq_file *)show->target, fmt, args);
>          |                             ^~~~~~~~
>    kernel/bpf/btf.c: In function 'btf_snprintf_show':
>    kernel/bpf/btf.c:6646:9: warning: function 'btf_snprintf_show' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
>     6646 |         len = vsnprintf(show->target, ssnprintf->len_left, fmt, args);
>          |         ^~~
> 
> 
> vim +/bpf_prog_inc_misses_counter +2310 include/linux/bpf.h
> 
>   2309	
> > 2310	static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
>   2311	{
>   2312	}
>   2313	#endif /* CONFIG_BPF_SYSCALL */
>   2314	#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */

hi,
I checked the linux-stable-rc.git queue/6.0 branch and it looks like the
backport patch shifted above inline stub into wrong ifdef block

with patch below I get it built

jirka


---
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e0feae308408..73662fbabd78 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2177,6 +2177,9 @@ static inline bool unprivileged_ebpf_enabled(void)
 	return false;
 }
 
+static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
+{
+}
 #endif /* CONFIG_BPF_SYSCALL */
 
 void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
@@ -2306,10 +2309,6 @@ static inline int sock_map_bpf_prog_query(const union bpf_attr *attr,
 {
 	return -EINVAL;
 }
-
-static inline void bpf_prog_inc_misses_counter(struct bpf_prog *prog)
-{
-}
 #endif /* CONFIG_BPF_SYSCALL */
 #endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */