Merge branch 'fix-compiler-warnings-looking-for-suggestions'

Rafael Passos says:

====================
Fix compiler warnings, looking for suggestions

Hi,
This patchset has a few fixes to compiler warnings.
I am studying the BPF subsystem and wish to bring more tangible contributions.
I would appreciate receiving suggestions on things to investigate.
I also documented a bit in my blog. I could help with docs here, too.
https://rcpassos.me/post/linux-ebpf-understanding-kernel-level-mechanics
Thanks!

Changelog V1 -> V2:
- rebased all commits to updated for-next base
- removes new cases of the extra parameter for bpf_jit_binary_pack_finalize
- built and tested for ARM64
- sent the series for the test workflow:
  https://github.com/kernel-patches/bpf/pull/7198
====================
Acked-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240615022641.210320-1-rafael@rcpassos.meSigned-off-by: Alexei Starovoitov <ast@kernel.org>

arch/arm64/net/bpf_jit_comp.c

@@ -1829,8 +1829,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 			prog->jited_len = 0;
 			goto out_free_hdr;
 		}
-		if (WARN_ON(bpf_jit_binary_pack_finalize(prog, ro_header,
-							 header))) {
+		if (WARN_ON(bpf_jit_binary_pack_finalize(ro_header, header))) {
 			/* ro_header has been freed */
 			ro_header = NULL;
 			prog = orig_prog;

arch/powerpc/net/bpf_jit_comp.c

@@ -225,7 +225,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
 	fp->jited_len = proglen + FUNCTION_DESCR_SIZE;
 
 	if (!fp->is_func || extra_pass) {
-		if (bpf_jit_binary_pack_finalize(fp, fhdr, hdr)) {
+		if (bpf_jit_binary_pack_finalize(fhdr, hdr)) {
 			fp = org_fp;
 			goto out_addrs;
 		}
@@ -348,7 +348,7 @@ void bpf_jit_free(struct bpf_prog *fp)
 		 * before freeing it.
 		 */
 		if (jit_data) {
-			bpf_jit_binary_pack_finalize(fp, jit_data->fhdr, jit_data->hdr);
+			bpf_jit_binary_pack_finalize(jit_data->fhdr, jit_data->hdr);
 			kvfree(jit_data->addrs);
 			kfree(jit_data);
 		}

arch/riscv/net/bpf_jit_core.c

@@ -178,8 +178,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 	prog->jited_len = prog_size - cfi_get_offset();
 
 	if (!prog->is_func || extra_pass) {
-		if (WARN_ON(bpf_jit_binary_pack_finalize(prog, jit_data->ro_header,
-							 jit_data->header))) {
+		if (WARN_ON(bpf_jit_binary_pack_finalize(jit_data->ro_header, jit_data->header))) {
 			/* ro_header has been freed */
 			jit_data->ro_header = NULL;
 			prog = orig_prog;
@@ -258,7 +257,7 @@ void bpf_jit_free(struct bpf_prog *prog)
 		 * before freeing it.
 		 */
 		if (jit_data) {
-			bpf_jit_binary_pack_finalize(prog, jit_data->ro_header, jit_data->header);
+			bpf_jit_binary_pack_finalize(jit_data->ro_header, jit_data->header);
 			kfree(jit_data);
 		}
 		hdr = bpf_jit_binary_pack_hdr(prog);

arch/x86/net/bpf_jit_comp.c

@@ -3356,7 +3356,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 			 *
 			 * Both cases are serious bugs and justify WARN_ON.
 			 */
-			if (WARN_ON(bpf_jit_binary_pack_finalize(prog, header, rw_header))) {
+			if (WARN_ON(bpf_jit_binary_pack_finalize(header, rw_header))) {
 				/* header has been freed */
 				header = NULL;
 				goto out_image;
@@ -3435,7 +3435,7 @@ void bpf_jit_free(struct bpf_prog *prog)
 		 * before freeing it.
 		 */
 		if (jit_data) {
-			bpf_jit_binary_pack_finalize(prog, jit_data->header,
+			bpf_jit_binary_pack_finalize(jit_data->header,
 						     jit_data->rw_header);
 			kvfree(jit_data->addrs);
 			kfree(jit_data);

include/linux/bpf.h

@@ -2933,8 +2933,7 @@ bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
 	return ret;
 }
 
-void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
-			  struct btf_mod_pair *used_btfs, u32 len);
+void __bpf_free_used_btfs(struct btf_mod_pair *used_btfs, u32 len);
 
 static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
 						 enum bpf_prog_type type)

include/linux/filter.h

@@ -1129,8 +1129,7 @@ bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **ro_image,
 			  struct bpf_binary_header **rw_hdr,
 			  u8 **rw_image,
 			  bpf_jit_fill_hole_t bpf_fill_ill_insns);
-int bpf_jit_binary_pack_finalize(struct bpf_prog *prog,
-				 struct bpf_binary_header *ro_header,
+int bpf_jit_binary_pack_finalize(struct bpf_binary_header *ro_header,
 				 struct bpf_binary_header *rw_header);
 void bpf_jit_binary_pack_free(struct bpf_binary_header *ro_header,
 			      struct bpf_binary_header *rw_header);

kernel/bpf/core.c

@@ -1174,8 +1174,7 @@ bpf_jit_binary_pack_alloc(unsigned int proglen, u8 **image_ptr,
 }
 
 /* Copy JITed text from rw_header to its final location, the ro_header. */
-int bpf_jit_binary_pack_finalize(struct bpf_prog *prog,
-				 struct bpf_binary_header *ro_header,
+int bpf_jit_binary_pack_finalize(struct bpf_binary_header *ro_header,
 				 struct bpf_binary_header *rw_header)
 {
 	void *ptr;
@@ -2743,8 +2742,7 @@ static void bpf_free_used_maps(struct bpf_prog_aux *aux)
 	kfree(aux->used_maps);
 }
 
-void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
-			  struct btf_mod_pair *used_btfs, u32 len)
+void __bpf_free_used_btfs(struct btf_mod_pair *used_btfs, u32 len)
 {
 #ifdef CONFIG_BPF_SYSCALL
 	struct btf_mod_pair *btf_mod;
@@ -2761,7 +2759,7 @@ void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
 
 static void bpf_free_used_btfs(struct bpf_prog_aux *aux)
 {
-	__bpf_free_used_btfs(aux, aux->used_btfs, aux->used_btf_cnt);
+	__bpf_free_used_btfs(aux->used_btfs, aux->used_btf_cnt);
 	kfree(aux->used_btfs);
 }
 

kernel/bpf/log.c

@@ -91,7 +91,7 @@ void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt,
 			goto fail;
 	} else {
 		u64 new_end, new_start;
-		u32 buf_start, buf_end, new_n;
+		u32 buf_start, buf_end;
 
 		new_end = log->end_pos + n;
 		if (new_end - log->start_pos >= log->len_total)

kernel/bpf/verifier.c

@@ -18694,8 +18694,7 @@ static void release_maps(struct bpf_verifier_env *env)
 /* drop refcnt of maps used by the rejected program */
 static void release_btfs(struct bpf_verifier_env *env)
 {
-	__bpf_free_used_btfs(env->prog->aux, env->used_btfs,
-			     env->used_btf_cnt);
+	__bpf_free_used_btfs(env->used_btfs, env->used_btf_cnt);
 }
 
 /* convert pseudo BPF_LD_IMM64 into generic BPF_LD_IMM64 */