[PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Andrii Nakryiko]

Building libbpf with -Wall (as happens via bpftool's bootstrap build)
surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
don't match their argument types: %d for __u32/Elf64_Word, %u for signed
ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
signed values.

Match each specifier to its argument's type where a correctly-signed
specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
which have no signed form, cast the argument instead (%x->(unsigned),
%lx->(unsigned long), %llx->(unsigned long long)). No functional change.

Note, the fdinfo map_flags sscanf used %i into a __u32 *, which warns.
The kernel prints map_flags as hex ("map_flags:\t%#x\n" in
bpf_map_show_fdinfo(), unchanged since the field was added to fdinfo), so
switch the conversion to %x: it parses the 0x-prefixed value and expects
unsigned int *, matching the destination, so the warning is gone with no
cast.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/lib/bpf/btf.c          | 10 ++---
 tools/lib/bpf/btf_dump.c     |  4 +-
 tools/lib/bpf/btf_relocate.c |  8 ++--
 tools/lib/bpf/elf.c          |  2 +-
 tools/lib/bpf/gen_loader.c   | 16 ++++----
 tools/lib/bpf/libbpf.c       | 78 ++++++++++++++++++------------------
 tools/lib/bpf/nlattr.c       |  2 +-
 tools/lib/bpf/relo_core.c    | 22 +++++-----
 tools/lib/bpf/usdt.c         | 33 ++++++++-------
 9 files changed, 89 insertions(+), 86 deletions(-)

diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 823bce895178..bf6a68118405 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -589,7 +589,7 @@ static int btf_parse_type_sec(struct btf *btf)
 		if (type_size < 0)
 			return type_size;
 		if (next_type + type_size > end_type) {
-			pr_warn("BTF type [%d] is malformed\n", btf->start_id + btf->nr_types);
+			pr_warn("BTF type [%u] is malformed\n", btf->start_id + btf->nr_types);
 			return -EINVAL;
 		}
 
@@ -1424,7 +1424,7 @@ static int btf_find_elf_sections(Elf *elf, const char *path, struct btf_elf_secs
 			continue;
 
 		if (sh.sh_type != SHT_PROGBITS) {
-			pr_warn("unexpected section type (%d) of section(%d, %s) from %s\n",
+			pr_warn("unexpected section type (%u) of section(%d, %s) from %s\n",
 				sh.sh_type, idx, name, path);
 			goto err;
 		}
@@ -4854,7 +4854,7 @@ static bool btf_dedup_identical_types(struct btf_dedup *d, __u32 id1, __u32 id2,
 				continue;
 			if (!btf_dedup_identical_types(d, m1->type, m2->type, depth - 1)) {
 				if (t1->name_off) {
-					pr_debug("%s '%s' size=%d vlen=%d id1[%u] id2[%u] shallow-equal but not identical for field#%d '%s'\n",
+					pr_debug("%s '%s' size=%u vlen=%u id1[%u] id2[%u] shallow-equal but not identical for field#%d '%s'\n",
 						 k1 == BTF_KIND_STRUCT ? "STRUCT" : "UNION",
 						 btf__name_by_offset(d->btf, t1->name_off),
 						 t1->size, btf_vlen(t1), id1, id2, i,
@@ -5104,7 +5104,7 @@ static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id,
 			eq = btf_dedup_is_equiv(d, cand_m->type, canon_m->type);
 			if (eq <= 0) {
 				if (cand_type->name_off) {
-					pr_debug("%s '%s' size=%d vlen=%d cand_id[%u] canon_id[%u] shallow-equal but not equiv for field#%d '%s': %d\n",
+					pr_debug("%s '%s' size=%u vlen=%u cand_id[%u] canon_id[%u] shallow-equal but not equiv for field#%d '%s': %d\n",
 						 cand_kind == BTF_KIND_STRUCT ? "STRUCT" : "UNION",
 						 btf__name_by_offset(d->btf, cand_type->name_off),
 						 cand_type->size, vlen, cand_id, canon_id, i,
@@ -6069,7 +6069,7 @@ static int btf_add_distilled_types(struct btf_distill *dist)
 			err = btf_add_type(&dist->pipe, t);
 			break;
 		default:
-			pr_warn("unexpected kind when adding base type '%s'[%u] of kind [%u] to distilled base BTF.\n",
+			pr_warn("unexpected kind when adding base type '%s'[%d] of kind [%d] to distilled base BTF.\n",
 				name, i, kind);
 			return -EINVAL;
 
diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
index cc1ba65bb6c5..123c448f20c7 100644
--- a/tools/lib/bpf/btf_dump.c
+++ b/tools/lib/bpf/btf_dump.c
@@ -1776,7 +1776,7 @@ static int btf_dump_get_bitfield_value(struct btf_dump *d,
 
 	/* Maximum supported bitfield size is 64 bits */
 	if (t->size > 8) {
-		pr_warn("unexpected bitfield size %d\n", t->size);
+		pr_warn("unexpected bitfield size %u\n", t->size);
 		return -EINVAL;
 	}
 
@@ -2251,7 +2251,7 @@ static int btf_dump_get_enum_value(struct btf_dump *d,
 		*value = is_signed ? *(__s8 *)data : *(__u8 *)data;
 		return 0;
 	default:
-		pr_warn("unexpected size %d for enum, id:[%u]\n", t->size, id);
+		pr_warn("unexpected size %u for enum, id:[%u]\n", t->size, id);
 		return -EINVAL;
 	}
 }
diff --git a/tools/lib/bpf/btf_relocate.c b/tools/lib/bpf/btf_relocate.c
index 53d1f3541bce..df5fa4bd87d6 100644
--- a/tools/lib/bpf/btf_relocate.c
+++ b/tools/lib/bpf/btf_relocate.c
@@ -280,7 +280,7 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r)
 		     cmp_btf_name_size(&base_info, dist_info) == 0;
 		     dist_info++) {
 			if (!dist_info->id || dist_info->id >= r->nr_dist_base_types) {
-				pr_warn("base BTF id [%d] maps to invalid distilled base BTF id [%d]\n",
+				pr_warn("base BTF id [%u] maps to invalid distilled base BTF id [%u]\n",
 					id, dist_info->id);
 				err = -EINVAL;
 				goto done;
@@ -368,7 +368,7 @@ static int btf_relocate_map_distilled_base(struct btf_relocate *r)
 			continue;
 		dist_t = btf_type_by_id(r->dist_base_btf, id);
 		name = btf__name_by_offset(r->dist_base_btf, dist_t->name_off);
-		pr_warn("distilled base BTF type '%s' [%d] is not mapped to base BTF id\n",
+		pr_warn("distilled base BTF type '%s' [%u] is not mapped to base BTF id\n",
 			name, id);
 		err = -EINVAL;
 		break;
@@ -397,11 +397,11 @@ static int btf_relocate_validate_distilled_base(struct btf_relocate *r)
 		case BTF_KIND_FWD:
 			if (t->name_off)
 				break;
-			pr_warn("type [%d], kind [%d] is invalid for distilled base BTF; it is anonymous\n",
+			pr_warn("type [%u], kind [%d] is invalid for distilled base BTF; it is anonymous\n",
 				i, kind);
 			return -EINVAL;
 		default:
-			pr_warn("type [%d] in distilled based BTF has unexpected kind [%d]\n",
+			pr_warn("type [%u] in distilled based BTF has unexpected kind [%d]\n",
 				i, kind);
 			return -EINVAL;
 		}
diff --git a/tools/lib/bpf/elf.c b/tools/lib/bpf/elf.c
index 295dbda24580..fe136d025967 100644
--- a/tools/lib/bpf/elf.c
+++ b/tools/lib/bpf/elf.c
@@ -354,7 +354,7 @@ long elf_find_func_offset(Elf *elf, const char *binary_path, const char *name)
 
 	if (ret > 0) {
 		pr_debug("elf: symbol address match for '%s' in '%s': 0x%lx\n", name, binary_path,
-			 ret);
+			 (unsigned long)ret);
 	} else {
 		if (ret == 0) {
 			pr_warn("elf: '%s' is 0 in symtab for '%s': %s\n", name, binary_path,
diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c
index d79695f01c87..c7f2d2ac7bb3 100644
--- a/tools/lib/bpf/gen_loader.c
+++ b/tools/lib/bpf/gen_loader.c
@@ -384,7 +384,7 @@ int bpf_gen__finish(struct bpf_gen *gen, int nr_progs, int nr_maps)
 	int i;
 
 	if (nr_progs < gen->nr_progs || nr_maps != gen->nr_maps) {
-		pr_warn("nr_progs %d/%d nr_maps %d/%d mismatch\n",
+		pr_warn("nr_progs %d/%u nr_maps %d/%u mismatch\n",
 			nr_progs, gen->nr_progs, nr_maps, gen->nr_maps);
 		gen->error = -EFAULT;
 		return gen->error;
@@ -488,7 +488,7 @@ void bpf_gen__load_btf(struct bpf_gen *gen, const void *btf_raw_data,
 
 	attr.btf_size = tgt_endian(btf_raw_size);
 	btf_load_attr = add_data(gen, &attr, attr_size);
-	pr_debug("gen: load_btf: off %d size %d, attr: off %d size %d\n",
+	pr_debug("gen: load_btf: off %d size %u, attr: off %d size %d\n",
 		 btf_data, btf_raw_size, btf_load_attr, attr_size);
 
 	/* populate union bpf_attr with user provided log details */
@@ -534,7 +534,7 @@ void bpf_gen__map_create(struct bpf_gen *gen,
 	attr.btf_value_type_id = tgt_endian(map_attr->btf_value_type_id);
 
 	map_create_attr = add_data(gen, &attr, attr_size);
-	pr_debug("gen: map_create: %s idx %d type %d value_type_id %d, attr: off %d size %d\n",
+	pr_debug("gen: map_create: %s idx %d type %u value_type_id %u, attr: off %d size %d\n",
 		 map_name, map_idx, map_type, map_attr->btf_value_type_id,
 		 map_create_attr, attr_size);
 
@@ -1082,7 +1082,7 @@ void bpf_gen__prog_load(struct bpf_gen *gen,
 	license_off = add_data(gen, license, strlen(license) + 1);
 	/* add insns to blob of bytes */
 	insns_off = add_data(gen, insns, insn_cnt * sizeof(struct bpf_insn));
-	pr_debug("gen: prog_load: prog_idx %d type %d insn off %d insns_cnt %zd license off %d\n",
+	pr_debug("gen: prog_load: prog_idx %d type %u insn off %d insns_cnt %zu license off %d\n",
 		 prog_idx, prog_type, insns_off, insn_cnt, license_off);
 
 	/* convert blob insns to target endianness */
@@ -1105,21 +1105,21 @@ void bpf_gen__prog_load(struct bpf_gen *gen,
 	attr.func_info_rec_size = tgt_endian(load_attr->func_info_rec_size);
 	attr.func_info_cnt = tgt_endian(load_attr->func_info_cnt);
 	func_info = add_data(gen, load_attr->func_info, func_info_tot_sz);
-	pr_debug("gen: prog_load: func_info: off %d cnt %d rec size %d\n",
+	pr_debug("gen: prog_load: func_info: off %d cnt %u rec size %u\n",
 		 func_info, load_attr->func_info_cnt,
 		 load_attr->func_info_rec_size);
 
 	attr.line_info_rec_size = tgt_endian(load_attr->line_info_rec_size);
 	attr.line_info_cnt = tgt_endian(load_attr->line_info_cnt);
 	line_info = add_data(gen, load_attr->line_info, line_info_tot_sz);
-	pr_debug("gen: prog_load: line_info: off %d cnt %d rec size %d\n",
+	pr_debug("gen: prog_load: line_info: off %d cnt %u rec size %u\n",
 		 line_info, load_attr->line_info_cnt,
 		 load_attr->line_info_rec_size);
 
 	attr.core_relo_rec_size = tgt_endian((__u32)sizeof(struct bpf_core_relo));
 	attr.core_relo_cnt = tgt_endian(gen->core_relo_cnt);
 	core_relos = add_data(gen, gen->core_relos, core_relo_tot_sz);
-	pr_debug("gen: prog_load: core_relos: off %d cnt %d rec size %zd\n",
+	pr_debug("gen: prog_load: core_relos: off %d cnt %d rec size %zu\n",
 		 core_relos, gen->core_relo_cnt,
 		 sizeof(struct bpf_core_relo));
 
@@ -1234,7 +1234,7 @@ void bpf_gen__map_update_elem(struct bpf_gen *gen, int map_idx, void *pvalue,
 	}
 
 	map_update_attr = add_data(gen, &attr, attr_size);
-	pr_debug("gen: map_update_elem: idx %d, value: off %d size %d, attr: off %d size %d\n",
+	pr_debug("gen: map_update_elem: idx %d, value: off %d size %u, attr: off %d size %d\n",
 		 map_idx, value, value_size, map_update_attr, attr_size);
 	move_blob2blob(gen, attr_field(map_update_attr, map_fd), 4,
 		       blob_fd_array_off(gen, map_idx));
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ab2071fdd3e8..1820a7c24e53 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1481,7 +1481,7 @@ static int init_struct_ops_maps(struct bpf_object *obj, const char *sec_name,
 		       type->size);
 		st_ops->type_id = type_id;
 
-		pr_debug("struct_ops init: struct %s(type_id=%u) %s found at offset %u\n",
+		pr_debug("struct_ops init: struct %s(type_id=%d) %s found at offset %u\n",
 			 tname, type_id, var_name, vsi->offset);
 	}
 
@@ -2621,7 +2621,7 @@ int parse_btf_map_def(const char *map_name, struct btf *btf,
 
 			t = btf__type_by_id(btf, m->type);
 			if (!t) {
-				pr_warn("map '%s': key type [%d] not found.\n",
+				pr_warn("map '%s': key type [%u] not found.\n",
 					map_name, m->type);
 				return -EINVAL;
 			}
@@ -2661,7 +2661,7 @@ int parse_btf_map_def(const char *map_name, struct btf *btf,
 
 			t = btf__type_by_id(btf, m->type);
 			if (!t) {
-				pr_warn("map '%s': value type [%d] not found.\n",
+				pr_warn("map '%s': value type [%u] not found.\n",
 					map_name, m->type);
 				return -EINVAL;
 			}
@@ -2715,7 +2715,7 @@ int parse_btf_map_def(const char *map_name, struct btf *btf,
 			map_def->value_size = 4;
 			t = btf__type_by_id(btf, m->type);
 			if (!t) {
-				pr_warn("map '%s': %s type [%d] not found.\n",
+				pr_warn("map '%s': %s type [%u] not found.\n",
 					map_name, desc, m->type);
 				return -EINVAL;
 			}
@@ -3471,7 +3471,7 @@ static int btf_fixup_datasec(struct bpf_object *obj, struct btf *btf,
 
 		var_name = btf__name_by_offset(btf, t_var->name_off);
 		if (!var_name) {
-			pr_debug("sec '%s': failed to find name of DATASEC's member #%d\n",
+			pr_debug("sec '%s': failed to find name of DATASEC's member #%u\n",
 				 sec_name, i);
 			return -ENOENT;
 		}
@@ -3966,7 +3966,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
 		if (!data)
 			return -LIBBPF_ERRNO__FORMAT;
 
-		pr_debug("elf: section(%d) %s, size %ld, link %d, flags %lx, type=%d\n",
+		pr_debug("elf: section(%d) %s, size %lu, link %d, flags %lx, type=%d\n",
 			 idx, name, (unsigned long)data->d_size,
 			 (int)sh->sh_link, (unsigned long)sh->sh_flags,
 			 (int)sh->sh_type);
@@ -4489,7 +4489,7 @@ static int bpf_object__collect_externs(struct bpf_object *obj)
 
 			ext->kcfg.data_off = roundup(off, ext->kcfg.align);
 			off = ext->kcfg.data_off + ext->kcfg.sz;
-			pr_debug("extern (kcfg) #%d: symbol %d, off %u, name %s\n",
+			pr_debug("extern (kcfg) #%d: symbol %d, off %d, name %s\n",
 				 i, ext->sym_idx, ext->kcfg.data_off, ext->name);
 		}
 		sec->size = off;
@@ -4621,7 +4621,7 @@ static int bpf_program__record_reloc(struct bpf_program *prog,
 	struct bpf_map *map;
 
 	if (!is_call_insn(insn) && !is_ldimm64_insn(insn)) {
-		pr_warn("prog '%s': invalid relo against '%s' for insns[%d].code 0x%x\n",
+		pr_warn("prog '%s': invalid relo against '%s' for insns[%u].code 0x%x\n",
 			prog->name, sym_name, insn_idx, insn->code);
 		return -LIBBPF_ERRNO__RELOC;
 	}
@@ -4744,7 +4744,7 @@ static int bpf_program__record_reloc(struct bpf_program *prog,
 			    map->sec_idx != sym->st_shndx ||
 			    map->sec_offset != sym->st_value)
 				continue;
-			pr_debug("prog '%s': found map %zd (%s, sec %d, off %zu) for insn #%u\n",
+			pr_debug("prog '%s': found map %zu (%s, sec %d, off %zu) for insn #%u\n",
 				 prog->name, map_idx, map->name, map->sec_idx,
 				 map->sec_offset, insn_idx);
 			break;
@@ -4771,7 +4771,7 @@ static int bpf_program__record_reloc(struct bpf_program *prog,
 		map = &obj->maps[map_idx];
 		if (map->libbpf_type != type || map->sec_idx != sym->st_shndx)
 			continue;
-		pr_debug("prog '%s': found data map %zd (%s, sec %d, off %zu) for insn %u\n",
+		pr_debug("prog '%s': found data map %zu (%s, sec %d, off %zu) for insn %u\n",
 			 prog->name, map_idx, map->name, map->sec_idx,
 			 map->sec_offset, insn_idx);
 		break;
@@ -4980,7 +4980,7 @@ static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info)
 			info->value_size = val;
 		else if (sscanf(buff, "max_entries:\t%u", &val) == 1)
 			info->max_entries = val;
-		else if (sscanf(buff, "map_flags:\t%i", &val) == 1)
+		else if (sscanf(buff, "map_flags:\t%x", &val) == 1)
 			info->map_flags = val;
 	}
 
@@ -5516,11 +5516,11 @@ static int init_map_in_map_slots(struct bpf_object *obj, struct bpf_map *map)
 		}
 		if (err) {
 			err = -errno;
-			pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %s\n",
+			pr_warn("map '%s': failed to initialize slot [%u] to map '%s' fd=%d: %s\n",
 				map->name, i, targ_map->name, fd, errstr(err));
 			return err;
 		}
-		pr_debug("map '%s': slot [%d] set to map '%s' fd=%d\n",
+		pr_debug("map '%s': slot [%u] set to map '%s' fd=%d\n",
 			 map->name, i, targ_map->name, fd);
 	}
 
@@ -5549,11 +5549,11 @@ static int init_prog_array_slots(struct bpf_object *obj, struct bpf_map *map)
 		err = bpf_map_update_elem(map->fd, &i, &fd, 0);
 		if (err) {
 			err = -errno;
-			pr_warn("map '%s': failed to initialize slot [%d] to prog '%s' fd=%d: %s\n",
+			pr_warn("map '%s': failed to initialize slot [%u] to prog '%s' fd=%d: %s\n",
 				map->name, i, targ_prog->name, fd, errstr(err));
 			return err;
 		}
-		pr_debug("map '%s': slot [%d] set to prog '%s' fd=%d\n",
+		pr_debug("map '%s': slot [%u] set to prog '%s' fd=%d\n",
 			 map->name, i, targ_prog->name, fd);
 	}
 
@@ -5783,7 +5783,7 @@ int bpf_core_add_cands(struct bpf_core_cand *local_cand,
 		if (strncmp(local_name, targ_name, local_essent_len) != 0)
 			continue;
 
-		pr_debug("CO-RE relocating [%d] %s %s: found target candidate [%d] %s %s in [%s]\n",
+		pr_debug("CO-RE relocating [%u] %s %s: found target candidate [%d] %s %s in [%s]\n",
 			 local_cand->id, btf_kind_str(local_t),
 			 local_name, i, btf_kind_str(t), targ_name,
 			 targ_btf_name);
@@ -5843,7 +5843,7 @@ static int load_module_btfs(struct bpf_object *obj)
 			if (errno == ENOENT)
 				continue; /* expected race: BTF was unloaded */
 			err = -errno;
-			pr_warn("failed to get BTF object #%d FD: %s\n", id, errstr(err));
+			pr_warn("failed to get BTF object #%u FD: %s\n", id, errstr(err));
 			return err;
 		}
 
@@ -5856,7 +5856,7 @@ static int load_module_btfs(struct bpf_object *obj)
 		err = bpf_btf_get_info_by_fd(fd, &info, &len);
 		if (err) {
 			err = -errno;
-			pr_warn("failed to get BTF object #%d info: %s\n", id, errstr(err));
+			pr_warn("failed to get BTF object #%u info: %s\n", id, errstr(err));
 			break;
 		}
 
@@ -5869,7 +5869,7 @@ static int load_module_btfs(struct bpf_object *obj)
 		btf = btf_get_from_fd(fd, obj->btf_vmlinux);
 		err = libbpf_get_error(btf);
 		if (err) {
-			pr_warn("failed to load module [%s]'s BTF object #%d: %s\n",
+			pr_warn("failed to load module [%s]'s BTF object #%u: %s\n",
 				name, id, errstr(err));
 			break;
 		}
@@ -6062,7 +6062,7 @@ static int bpf_core_resolve_relo(struct bpf_program *prog,
 	    !hashmap__find(cand_cache, local_id, &cands)) {
 		cands = bpf_core_find_cands(prog->obj, local_btf, local_id);
 		if (IS_ERR(cands)) {
-			pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld\n",
+			pr_warn("prog '%s': relo #%d: target candidate search failed for [%u] %s %s: %ld\n",
 				prog_name, relo_idx, local_id, btf_kind_str(local_type),
 				local_name, PTR_ERR(cands));
 			return PTR_ERR(cands);
@@ -6122,7 +6122,7 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path)
 			goto out;
 		}
 
-		pr_debug("sec '%s': found %d CO-RE relocations\n", sec_name, sec->num_info);
+		pr_debug("sec '%s': found %u CO-RE relocations\n", sec_name, sec->num_info);
 
 		for_each_btf_ext_rec(seg, sec, i, rec) {
 			if (rec->insn_off % BPF_INSN_SZ)
@@ -6176,7 +6176,7 @@ bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path)
 
 			err = bpf_core_patch_insn(prog->name, insn, insn_idx, rec, i, &targ_res);
 			if (err) {
-				pr_warn("prog '%s': relo #%d: failed to patch insn #%u: %s\n",
+				pr_warn("prog '%s': relo #%d: failed to patch insn #%d: %s\n",
 					prog->name, i, insn_idx, errstr(err));
 				goto out;
 			}
@@ -6341,7 +6341,7 @@ static int create_jt_map(struct bpf_object *obj, struct bpf_program *prog, struc
 		goto err_close;
 	}
 	if (sym_off + jt_size > obj->jumptables_data_sz) {
-		pr_warn("map '.jumptables': jumptables_data size is %zd, trying to access %d\n",
+		pr_warn("map '.jumptables': jumptables_data size is %zu, trying to access %u\n",
 			obj->jumptables_data_sz, sym_off + jt_size);
 		err = -EINVAL;
 		goto err_close;
@@ -6376,7 +6376,7 @@ static int create_jt_map(struct bpf_object *obj, struct bpf_program *prog, struc
 		 */
 		if (insn_off > UINT32_MAX) {
 			pr_warn("map '.jumptables': invalid jump table value 0x%llx at offset %u\n",
-				(long long)jt[i], sym_off + i * jt_entry_size);
+				(unsigned long long)jt[i], sym_off + i * jt_entry_size);
 			err = -EINVAL;
 			goto err_close;
 		}
@@ -6512,7 +6512,7 @@ bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog)
 		}
 			break;
 		default:
-			pr_warn("prog '%s': relo #%d: bad relo type %d\n",
+			pr_warn("prog '%s': relo #%d: bad relo type %u\n",
 				prog->name, i, relo->type);
 			return -EINVAL;
 		}
@@ -6792,7 +6792,7 @@ bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog,
 			 */
 			continue;
 		if (relo && relo->type != RELO_CALL && relo->type != RELO_SUBPROG_ADDR) {
-			pr_warn("prog '%s': unexpected relo for insn #%zu, type %d\n",
+			pr_warn("prog '%s': unexpected relo for insn #%zu, type %u\n",
 				prog->name, insn_idx, relo->type);
 			return -LIBBPF_ERRNO__RELOC;
 		}
@@ -7582,7 +7582,7 @@ static int bpf_object__collect_map_relos(struct bpf_object *obj,
 		}
 		name = elf_sym_str(obj, sym->st_name) ?: "<?>";
 
-		pr_debug(".maps relo #%d: for %zd value %zd rel->r_offset %zu name %d ('%s')\n",
+		pr_debug(".maps relo #%d: for %zd value %zu rel->r_offset %zu name %u ('%s')\n",
 			 i, (ssize_t)(rel->r_info >> 32), (size_t)sym->st_value,
 			 (size_t)rel->r_offset, sym->st_name, name);
 
@@ -7673,7 +7673,7 @@ static int bpf_object__collect_map_relos(struct bpf_object *obj,
 		}
 		map->init_slots[moff] = is_map_in_map ? (void *)targ_map : (void *)targ_prog;
 
-		pr_debug(".maps relo #%d: map '%s' slot [%d] points to %s '%s'\n",
+		pr_debug(".maps relo #%d: map '%s' slot [%u] points to %s '%s'\n",
 			 i, map->name, moff, type, name);
 	}
 
@@ -8658,7 +8658,7 @@ static int bpf_object__resolve_ksym_var_btf_id(struct bpf_object *obj,
 		local_name = btf__name_by_offset(obj->btf, local_type->name_off);
 		targ_name = btf__name_by_offset(btf, targ_type->name_off);
 
-		pr_warn("extern (var ksym) '%s': incompatible types, expected [%d] %s %s, but kernel has [%d] %s %s\n",
+		pr_warn("extern (var ksym) '%s': incompatible types, expected [%u] %s %s, but kernel has [%u] %s %s\n",
 			ext->name, local_type_id,
 			btf_kind_str(local_type), local_name, targ_type_id,
 			btf_kind_str(targ_type), targ_name);
@@ -8835,7 +8835,7 @@ static int bpf_object__resolve_externs(struct bpf_object *obj,
 			if (err)
 				return err;
 			pr_debug("extern (kcfg) '%s': set to 0x%llx\n",
-				 ext->name, (long long)value);
+				 ext->name, (unsigned long long)value);
 		} else {
 			pr_warn("extern '%s': unrecognized extern kind\n", ext->name);
 			return -EINVAL;
@@ -10399,7 +10399,7 @@ static int bpf_object__collect_st_ops_relos(struct bpf_object *obj,
 		moff = rel->r_offset - map->sec_offset;
 		shdr_idx = sym->st_shndx;
 		st_ops = map->st_ops;
-		pr_debug("struct_ops reloc %s: for %lld value %lld shdr_idx %u rel->r_offset %zu map->sec_offset %zu name %d (\'%s\')\n",
+		pr_debug("struct_ops reloc %s: for %lld value %lld shdr_idx %u rel->r_offset %zu map->sec_offset %zu name %u (\'%s\')\n",
 			 map->name,
 			 (long long)(rel->r_info >> 32),
 			 (long long)sym->st_value,
@@ -10548,7 +10548,7 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd, int t
 	memset(&info, 0, info_len);
 	err = bpf_prog_get_info_by_fd(attach_prog_fd, &info, &info_len);
 	if (err) {
-		pr_warn("failed bpf_prog_get_info_by_fd for FD %d: %s\n",
+		pr_warn("failed bpf_prog_get_info_by_fd for FD %u: %s\n",
 			attach_prog_fd, errstr(err));
 		return err;
 	}
@@ -10561,7 +10561,7 @@ static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd, int t
 	btf = btf_load_from_kernel(info.btf_id, NULL, token_fd);
 	err = libbpf_get_error(btf);
 	if (err) {
-		pr_warn("Failed to get BTF %d of the program: %s\n", info.btf_id, errstr(err));
+		pr_warn("Failed to get BTF %u of the program: %s\n", info.btf_id, errstr(err));
 		goto out;
 	}
 	err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC);
@@ -10643,7 +10643,7 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac
 		}
 		err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd, prog->obj->token_fd);
 		if (err < 0) {
-			pr_warn("prog '%s': failed to find BPF program (FD %d) BTF ID for '%s': %s\n",
+			pr_warn("prog '%s': failed to find BPF program (FD %u) BTF ID for '%s': %s\n",
 				prog->name, attach_prog_fd, attach_name, errstr(err));
 			return err;
 		}
@@ -11138,7 +11138,7 @@ static int validate_map_op(const struct bpf_map *map, size_t key_sz,
 		}
 
 		if (value_sz != num_cpu * elem_sz) {
-			pr_warn("map '%s': unexpected value size %zu provided for per-CPU map, expected %d * %zu = %zd\n",
+			pr_warn("map '%s': unexpected value size %zu provided for per-CPU map, expected %d * %zu = %zu\n",
 				map->name, value_sz, num_cpu, elem_sz, num_cpu * elem_sz);
 			return -EINVAL;
 		}
@@ -11679,7 +11679,7 @@ static void gen_probe_legacy_event_name(char *buf, size_t buf_sz,
 	static int index = 0;
 	int i;
 
-	snprintf(buf, buf_sz, "libbpf_%u_%d_%s_0x%zx", getpid(),
+	snprintf(buf, buf_sz, "libbpf_%d_%d_%s_0x%zx", getpid(),
 		 __sync_fetch_and_add(&index, 1), name, offset);
 
 	/* sanitize name in the probe name */
@@ -12556,8 +12556,8 @@ static long elf_find_func_offset_from_archive(const char *archive_path, const ch
 	ret = elf_find_func_offset(elf, file_name, func_name);
 	if (ret > 0) {
 		pr_debug("elf: symbol address match for %s of %s in %s: 0x%x + 0x%lx = 0x%lx\n",
-			 func_name, file_name, archive_path, entry.data_offset, ret,
-			 ret + entry.data_offset);
+			 func_name, file_name, archive_path, entry.data_offset, (unsigned long)ret,
+			 (unsigned long)(ret + entry.data_offset));
 		ret += entry.data_offset;
 	}
 	elf_end(elf);
@@ -14202,7 +14202,7 @@ perf_buffer__process_record(struct perf_event_header *e, void *ctx)
 		break;
 	}
 	default:
-		pr_warn("unknown perf sample type %d\n", e->type);
+		pr_warn("unknown perf sample type %u\n", e->type);
 		return LIBBPF_PERF_EVENT_ERROR;
 	}
 	return LIBBPF_PERF_EVENT_CONT;
diff --git a/tools/lib/bpf/nlattr.c b/tools/lib/bpf/nlattr.c
index 06663f9ea581..007fe17d17b4 100644
--- a/tools/lib/bpf/nlattr.c
+++ b/tools/lib/bpf/nlattr.c
@@ -123,7 +123,7 @@ int libbpf_nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head,
 
 		if (tb[type]) {
 			pr_warn("Attribute of type %#x found multiple times in message, "
-				"previous attribute is being ignored.\n", type);
+				"previous attribute is being ignored.\n", (unsigned)type);
 		}
 
 		tb[type] = nla;
diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c
index 6ae3f2a15ad0..8ad2715721cf 100644
--- a/tools/lib/bpf/relo_core.c
+++ b/tools/lib/bpf/relo_core.c
@@ -216,7 +216,7 @@ int __bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
 		goto recur;
 	}
 	default:
-		pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n",
+		pr_warn("unexpected kind %s relocated, local [%u], target [%u]\n",
 			btf_kind_str(local_type), local_id, targ_id);
 		return 0;
 	}
@@ -384,7 +384,7 @@ int bpf_core_parse_spec(const char *prog_name, const struct btf *btf,
 				return sz;
 			spec->bit_offset += access_idx * sz * 8;
 		} else {
-			pr_warn("prog '%s': relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %s\n",
+			pr_warn("prog '%s': relo for [%u] %s (at idx %d) captures type [%u] of unexpected kind %s\n",
 				prog_name, relo->type_id, spec_str, i, id, btf_kind_str(t));
 			return -EINVAL;
 		}
@@ -725,7 +725,7 @@ static int bpf_core_calc_field_relo(const char *prog_name,
 				return -EINVAL;
 			*val = sz;
 		} else {
-			pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n",
+			pr_warn("prog '%s': relo %u at insn #%u can't be applied to array access\n",
 				prog_name, relo->kind, relo->insn_off / 8);
 			return -EINVAL;
 		}
@@ -747,7 +747,7 @@ static int bpf_core_calc_field_relo(const char *prog_name,
 		while (bit_off + bit_sz - byte_off * 8 > byte_sz * 8) {
 			if (byte_sz >= 8) {
 				/* bitfield can't be read with 64-bit read */
-				pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n",
+				pr_warn("prog '%s': relo %u at insn #%u can't be satisfied for bitfield\n",
 					prog_name, relo->kind, relo->insn_off / 8);
 				return -E2BIG;
 			}
@@ -971,7 +971,7 @@ static int bpf_core_calc_relo(const char *prog_name,
 		err = 0;
 	} else if (err == -EOPNOTSUPP) {
 		/* EOPNOTSUPP means unknown/unsupported relocation */
-		pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n",
+		pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%u) at insn #%u\n",
 			prog_name, relo_idx, core_relo_kind_str(relo->kind),
 			relo->kind, relo->insn_off / 8);
 	}
@@ -1067,7 +1067,7 @@ int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
 		if (BPF_SRC(insn->code) != BPF_K)
 			return -EINVAL;
 		if (res->validate && insn->imm != orig_val) {
-			pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %llu -> %llu\n",
+			pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %d, exp %llu -> %llu\n",
 				prog_name, relo_idx,
 				insn_idx, insn->imm, (unsigned long long)orig_val,
 				(unsigned long long)new_val);
@@ -1083,7 +1083,7 @@ int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
 	case BPF_ST:
 	case BPF_STX:
 		if (res->validate && insn->off != orig_val) {
-			pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %llu -> %llu\n",
+			pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %d, exp %llu -> %llu\n",
 				prog_name, relo_idx, insn_idx, insn->off, (unsigned long long)orig_val,
 				(unsigned long long)new_val);
 			return -EINVAL;
@@ -1159,7 +1159,7 @@ int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
 	default:
 		pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n",
 			prog_name, relo_idx, insn_idx, insn->code,
-			insn->src_reg, insn->dst_reg, insn->off, insn->imm);
+			(unsigned)insn->src_reg, (unsigned)insn->dst_reg, (unsigned)insn->off, (unsigned)insn->imm);
 		return -EINVAL;
 	}
 
@@ -1323,7 +1323,7 @@ int bpf_core_calc_relo_insn(const char *prog_name,
 		const char *spec_str;
 
 		spec_str = btf__name_by_offset(local_btf, relo->access_str_off);
-		pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n",
+		pr_warn("prog '%s': relo #%d: parsing [%u] %s %s + %s failed: %d\n",
 			prog_name, relo_idx, local_id, btf_kind_str(local_type),
 			str_is_empty(local_name) ? "<anon>" : local_name,
 			spec_str ?: "<?>", err);
@@ -1346,7 +1346,7 @@ int bpf_core_calc_relo_insn(const char *prog_name,
 
 	/* libbpf doesn't support candidate search for anonymous types */
 	if (str_is_empty(local_name)) {
-		pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n",
+		pr_warn("prog '%s': relo #%d: <%s> (%u) relocation doesn't support anonymous types\n",
 			prog_name, relo_idx, core_relo_kind_str(relo->kind), relo->kind);
 		return -EOPNOTSUPP;
 	}
@@ -1697,7 +1697,7 @@ int __bpf_core_types_match(const struct btf *local_btf, __u32 local_id, const st
 		goto recur;
 	}
 	default:
-		pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n",
+		pr_warn("unexpected kind %s relocated, local [%u], target [%u]\n",
 			btf_kind_str(local_t), local_id, targ_id);
 		return 0;
 	}
diff --git a/tools/lib/bpf/usdt.c b/tools/lib/bpf/usdt.c
index 57fb82bb81b5..db9432adb967 100644
--- a/tools/lib/bpf/usdt.c
+++ b/tools/lib/bpf/usdt.c
@@ -327,7 +327,7 @@ static int sanity_check_usdt_elf(Elf *elf, const char *path)
 	int endianness;
 
 	if (elf_kind(elf) != ELF_K_ELF) {
-		pr_warn("usdt: unrecognized ELF kind %d for '%s'\n", elf_kind(elf), path);
+		pr_warn("usdt: unrecognized ELF kind %u for '%s'\n", elf_kind(elf), path);
 		return -EBADF;
 	}
 
@@ -438,8 +438,9 @@ static int parse_elf_segs(Elf *elf, const char *path, struct elf_seg **segs, siz
 		}
 
 		pr_debug("usdt: discovered PHDR #%d in '%s': vaddr 0x%lx memsz 0x%lx offset 0x%lx type 0x%lx flags 0x%lx\n",
-			 i, path, (long)phdr.p_vaddr, (long)phdr.p_memsz, (long)phdr.p_offset,
-			 (long)phdr.p_type, (long)phdr.p_flags);
+			 i, path,
+			 (unsigned long)phdr.p_vaddr, (unsigned long)phdr.p_memsz, (unsigned long)phdr.p_offset,
+			 (unsigned long)phdr.p_type, (unsigned long)phdr.p_flags);
 		if (phdr.p_type != PT_LOAD)
 			continue;
 
@@ -719,14 +720,14 @@ static int collect_usdt_targets(struct usdt_manager *man, struct elf_fd *elf_fd,
 		if (!seg) {
 			err = -ESRCH;
 			pr_warn("usdt: failed to find ELF program segment for '%s:%s' in '%s' at IP 0x%lx\n",
-				usdt_provider, usdt_name, path, usdt_abs_ip);
+				usdt_provider, usdt_name, path, (unsigned long)usdt_abs_ip);
 			goto err_out;
 		}
 		if (!seg->is_exec) {
 			err = -ESRCH;
 			pr_warn("usdt: matched ELF binary '%s' segment [0x%lx, 0x%lx) for '%s:%s' at IP 0x%lx is not executable\n",
-				path, seg->start, seg->end, usdt_provider, usdt_name,
-				usdt_abs_ip);
+				path, (unsigned long)seg->start, (unsigned long)seg->end, usdt_provider, usdt_name,
+				(unsigned long)usdt_abs_ip);
 			goto err_out;
 		}
 		/* translate from virtual address to file offset */
@@ -766,7 +767,7 @@ static int collect_usdt_targets(struct usdt_manager *man, struct elf_fd *elf_fd,
 			if (!seg) {
 				err = -ESRCH;
 				pr_warn("usdt: failed to find shared lib memory segment for '%s:%s' in '%s' at relative IP 0x%lx\n",
-					usdt_provider, usdt_name, path, usdt_rel_ip);
+					usdt_provider, usdt_name, path, (unsigned long)usdt_rel_ip);
 				goto err_out;
 			}
 
@@ -775,8 +776,10 @@ static int collect_usdt_targets(struct usdt_manager *man, struct elf_fd *elf_fd,
 
 		pr_debug("usdt: probe for '%s:%s' in %s '%s': addr 0x%lx base 0x%lx (resolved abs_ip 0x%lx rel_ip 0x%lx) args '%s' in segment [0x%lx, 0x%lx) at offset 0x%lx\n",
 			 usdt_provider, usdt_name, ehdr.e_type == ET_EXEC ? "exec" : "lib ", path,
-			 note.loc_addr, note.base_addr, usdt_abs_ip, usdt_rel_ip, note.args,
-			 seg ? seg->start : 0, seg ? seg->end : 0, seg ? seg->offset : 0);
+			 (unsigned long)note.loc_addr, (unsigned long)note.base_addr,
+			 (unsigned long)usdt_abs_ip, (unsigned long)usdt_rel_ip, note.args,
+			 (unsigned long)(seg ? seg->start : 0), (unsigned long)(seg ? seg->end : 0),
+			 (unsigned long)(seg ? seg->offset : 0));
 
 		/* Adjust semaphore address to be a file offset */
 		if (note.sema_addr) {
@@ -791,14 +794,14 @@ static int collect_usdt_targets(struct usdt_manager *man, struct elf_fd *elf_fd,
 			if (!seg) {
 				err = -ESRCH;
 				pr_warn("usdt: failed to find ELF loadable segment with semaphore of '%s:%s' in '%s' at 0x%lx\n",
-					usdt_provider, usdt_name, path, note.sema_addr);
+					usdt_provider, usdt_name, path, (unsigned long)note.sema_addr);
 				goto err_out;
 			}
 			if (seg->is_exec) {
 				err = -ESRCH;
 				pr_warn("usdt: matched ELF binary '%s' segment [0x%lx, 0x%lx] for semaphore of '%s:%s' at 0x%lx is executable\n",
-					path, seg->start, seg->end, usdt_provider, usdt_name,
-					note.sema_addr);
+					path, (unsigned long)seg->start, (unsigned long)seg->end, usdt_provider, usdt_name,
+					(unsigned long)note.sema_addr);
 				goto err_out;
 			}
 
@@ -806,8 +809,8 @@ static int collect_usdt_targets(struct usdt_manager *man, struct elf_fd *elf_fd,
 
 			pr_debug("usdt: sema  for '%s:%s' in %s '%s': addr 0x%lx base 0x%lx (resolved 0x%lx) in segment [0x%lx, 0x%lx] at offset 0x%lx\n",
 				 usdt_provider, usdt_name, ehdr.e_type == ET_EXEC ? "exec" : "lib ",
-				 path, note.sema_addr, note.base_addr, usdt_sema_off,
-				 seg->start, seg->end, seg->offset);
+				 path, (unsigned long)note.sema_addr, (unsigned long)note.base_addr, (unsigned long)usdt_sema_off,
+				 (unsigned long)seg->start, (unsigned long)seg->end, (unsigned long)seg->offset);
 		}
 
 		/* Record adjusted addresses and offsets and parse USDT spec */
@@ -1117,7 +1120,7 @@ struct bpf_link *usdt_manager_attach_usdt(struct usdt_manager *man, const struct
 				        spec_id, usdt_provider, usdt_name, path);
 			} else {
 				pr_warn("usdt: failed to map IP 0x%lx to spec #%d for '%s:%s' in '%s': %s\n",
-					target->abs_ip, spec_id, usdt_provider, usdt_name,
+					(unsigned long)target->abs_ip, spec_id, usdt_provider, usdt_name,
 					path, errstr(err));
 			}
 			goto err_out;
-- 
2.53.0-Meta

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[bot+bpf-ci]

[-- Attachment #1: Type: text/plain, Size: 1316 bytes --]

> diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c
> index 0ccc8f548cba..8652c9b53720 100644
> --- a/tools/lib/bpf/relo_core.c
> +++ b/tools/lib/bpf/relo_core.c

[ ... ]

> @@ -1159,7 +1159,7 @@ int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
>  	default:
>  		pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n",
>  			prog_name, relo_idx, insn_idx, insn->code,
> -			insn->src_reg, insn->dst_reg, insn->off, insn->imm);
> +			(unsigned)insn->src_reg, (unsigned)insn->dst_reg, (unsigned)insn->off, (unsigned)insn->imm);

This isn't a bug, but src_reg, dst_reg, off and imm each picked up an
(unsigned) cast for their %x conversions here, while insn->code, also
printed with %x just above, was left as-is.

insn->code is a __u8 like src_reg and dst_reg, so it promotes to int and
hits the same %x/int mismatch the casts address for the others.  Was
leaving code uncast intentional, or should it get the (unsigned) cast too
for consistency within this statement?


---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md

CI run summary: https://github.com/kernel-patches/bpf/actions/runs/28211699373

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <ast@kernel.org>:

On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
> Building libbpf with -Wall (as happens via bpftool's bootstrap build)
> surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
> don't match their argument types: %d for __u32/Elf64_Word, %u for signed
> ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
> signed values.
> 
> Match each specifier to its argument's type where a correctly-signed
> specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
> which have no signed form, cast the argument instead (%x->(unsigned),
> %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
> 
> [...]

Here is the summary with links:
  - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
    https://git.kernel.org/bpf/bpf-next/c/df3153758ddb

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Andrii Nakryiko]

On Fri, Jun 26, 2026 at 6:30 AM <patchwork-bot+netdevbpf@kernel.org> wrote:
>
> Hello:
>
> This patch was applied to bpf/bpf-next.git (master)
> by Alexei Starovoitov <ast@kernel.org>:
>
> On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
> > Building libbpf with -Wall (as happens via bpftool's bootstrap build)
> > surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
> > don't match their argument types: %d for __u32/Elf64_Word, %u for signed
> > ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
> > signed values.
> >
> > Match each specifier to its argument's type where a correctly-signed
> > specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
> > which have no signed form, cast the argument instead (%x->(unsigned),
> > %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
> >
> > [...]
>
> Here is the summary with links:
>   - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
>     https://git.kernel.org/bpf/bpf-next/c/df3153758ddb
>

Quentin,

I synced these changes to libbpf's Github mirror. Can you please
update bpftool mirror's libbpf reference to include this change, so
that I can fix these noisy warnings for wprof? Thanks!

> You are awesome, thank you!
> --
> Deet-doot-dot, I am a bot.
> https://korg.docs.kernel.org/patchwork/pwbot.html
>
>

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Quentin Monnet]

2026-06-30 11:32 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
> On Fri, Jun 26, 2026 at 6:30 AM <patchwork-bot+netdevbpf@kernel.org> wrote:
>>
>> Hello:
>>
>> This patch was applied to bpf/bpf-next.git (master)
>> by Alexei Starovoitov <ast@kernel.org>:
>>
>> On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
>>> Building libbpf with -Wall (as happens via bpftool's bootstrap build)
>>> surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
>>> don't match their argument types: %d for __u32/Elf64_Word, %u for signed
>>> ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
>>> signed values.
>>>
>>> Match each specifier to its argument's type where a correctly-signed
>>> specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
>>> which have no signed form, cast the argument instead (%x->(unsigned),
>>> %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
>>>
>>> [...]
>>
>> Here is the summary with links:
>>   - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
>>     https://git.kernel.org/bpf/bpf-next/c/df3153758ddb
>>
> 
> Quentin,
> 
> I synced these changes to libbpf's Github mirror. Can you please
> update bpftool mirror's libbpf reference to include this change, so
> that I can fix these noisy warnings for wprof? Thanks!


Hi Andrii, I just synced it, thank you.

Quentin

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Andrii Nakryiko]

On Tue, Jun 30, 2026 at 1:01 PM Quentin Monnet <qmo@kernel.org> wrote:
>
> 2026-06-30 11:32 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
> > On Fri, Jun 26, 2026 at 6:30 AM <patchwork-bot+netdevbpf@kernel.org> wrote:
> >>
> >> Hello:
> >>
> >> This patch was applied to bpf/bpf-next.git (master)
> >> by Alexei Starovoitov <ast@kernel.org>:
> >>
> >> On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
> >>> Building libbpf with -Wall (as happens via bpftool's bootstrap build)
> >>> surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
> >>> don't match their argument types: %d for __u32/Elf64_Word, %u for signed
> >>> ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
> >>> signed values.
> >>>
> >>> Match each specifier to its argument's type where a correctly-signed
> >>> specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
> >>> which have no signed form, cast the argument instead (%x->(unsigned),
> >>> %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
> >>>
> >>> [...]
> >>
> >> Here is the summary with links:
> >>   - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
> >>     https://git.kernel.org/bpf/bpf-next/c/df3153758ddb
> >>
> >
> > Quentin,
> >
> > I synced these changes to libbpf's Github mirror. Can you please
> > update bpftool mirror's libbpf reference to include this change, so
> > that I can fix these noisy warnings for wprof? Thanks!
>
>
> Hi Andrii, I just synced it, thank you.
>

Thanks, Quentin!

I got a bunch of new ones with latest bpftool sync, I haven't looked
into it, but thought I'll mention in case it's something on bpftool's
Github Makefile side:

  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/btf_dump.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/hashmap.o
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/ringbuf.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/strset.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/linker.o
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/gen_loader.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/relo_core.o
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/usdt.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/zip.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/elf.o
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/features.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/btf_iter.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
  CC       /home/andriin/wprof/src/.output/bpftool/bootstrap/libbpf/staticobjs/btf_relocate.o
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]
cc1: warning: ‘-Wformat-y2k’ ignored without ‘-Wformat’ [-Wformat-y2k]
cc1: warning: ‘-Wformat-security’ ignored without ‘-Wformat’ [-Wformat-security]


> Quentin

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Quentin Monnet]

2026-06-30 13:15 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
> On Tue, Jun 30, 2026 at 1:01 PM Quentin Monnet <qmo@kernel.org> wrote:
>>
>> 2026-06-30 11:32 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
>>> On Fri, Jun 26, 2026 at 6:30 AM <patchwork-bot+netdevbpf@kernel.org> wrote:
>>>>
>>>> Hello:
>>>>
>>>> This patch was applied to bpf/bpf-next.git (master)
>>>> by Alexei Starovoitov <ast@kernel.org>:
>>>>
>>>> On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
>>>>> Building libbpf with -Wall (as happens via bpftool's bootstrap build)
>>>>> surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
>>>>> don't match their argument types: %d for __u32/Elf64_Word, %u for signed
>>>>> ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
>>>>> signed values.
>>>>>
>>>>> Match each specifier to its argument's type where a correctly-signed
>>>>> specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
>>>>> which have no signed form, cast the argument instead (%x->(unsigned),
>>>>> %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
>>>>>
>>>>> [...]
>>>>
>>>> Here is the summary with links:
>>>>   - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
>>>>     https://git.kernel.org/bpf/bpf-next/c/df3153758ddb
>>>>
>>>
>>> Quentin,
>>>
>>> I synced these changes to libbpf's Github mirror. Can you please
>>> update bpftool mirror's libbpf reference to include this change, so
>>> that I can fix these noisy warnings for wprof? Thanks!
>>
>>
>> Hi Andrii, I just synced it, thank you.
>>
> 
> Thanks, Quentin!
> 
> I got a bunch of new ones with latest bpftool sync, I haven't looked
> into it, but thought I'll mention in case it's something on bpftool's
> Github Makefile side:

[...]

Oh, I haven't observed these on my setup, I'll try to look into it when
I can. What compiler do you use? And do you see the same when compiling
from the kernel repo? The Makefiles should be rather close, in theory.

Quentin

Re: [PATCH bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches

[Andrii Nakryiko]

On Tue, Jun 30, 2026 at 1:37 PM Quentin Monnet <qmo@kernel.org> wrote:
>
> 2026-06-30 13:15 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
> > On Tue, Jun 30, 2026 at 1:01 PM Quentin Monnet <qmo@kernel.org> wrote:
> >>
> >> 2026-06-30 11:32 UTC-0700 ~ Andrii Nakryiko <andrii.nakryiko@gmail.com>
> >>> On Fri, Jun 26, 2026 at 6:30 AM <patchwork-bot+netdevbpf@kernel.org> wrote:
> >>>>
> >>>> Hello:
> >>>>
> >>>> This patch was applied to bpf/bpf-next.git (master)
> >>>> by Alexei Starovoitov <ast@kernel.org>:
> >>>>
> >>>> On Wed, 24 Jun 2026 13:49:46 -0700 you wrote:
> >>>>> Building libbpf with -Wall (as happens via bpftool's bootstrap build)
> >>>>> surfaces ~120 -Wformat warnings where pr_warn/pr_debug format specifiers
> >>>>> don't match their argument types: %d for __u32/Elf64_Word, %u for signed
> >>>>> ints, %zd for size_t, %ld for unsigned long, and %x/%lx/%llx applied to
> >>>>> signed values.
> >>>>>
> >>>>> Match each specifier to its argument's type where a correctly-signed
> >>>>> specifier exists (%d<->%u, %ld->%lu, %zd->%zu). For hex conversions,
> >>>>> which have no signed form, cast the argument instead (%x->(unsigned),
> >>>>> %lx->(unsigned long), %llx->(unsigned long long)). No functional change.
> >>>>>
> >>>>> [...]
> >>>>
> >>>> Here is the summary with links:
> >>>>   - [bpf-next] libbpf: fix -Wformat warnings from format/argument type mismatches
> >>>>     https://git.kernel.org/bpf/bpf-next/c/df3153758ddb
> >>>>
> >>>
> >>> Quentin,
> >>>
> >>> I synced these changes to libbpf's Github mirror. Can you please
> >>> update bpftool mirror's libbpf reference to include this change, so
> >>> that I can fix these noisy warnings for wprof? Thanks!
> >>
> >>
> >> Hi Andrii, I just synced it, thank you.
> >>
> >
> > Thanks, Quentin!
> >
> > I got a bunch of new ones with latest bpftool sync, I haven't looked
> > into it, but thought I'll mention in case it's something on bpftool's
> > Github Makefile side:
>
> [...]
>
> Oh, I haven't observed these on my setup, I'll try to look into it when
> I can. What compiler do you use? And do you see the same when compiling
> from the kernel repo? The Makefiles should be rather close, in theory.
>

Just sent a patch, bpftool's in-kernel Makefile needs a bit of
adjustment for boostrap version of bpftool. There is a note why we
don't see it in kernel build of bpftool (re-added -Wall masks this),
but I confirmed that with github libbpf Makefile and wprof setup the
issue is gone. Please take a look.

> Quentin