ERROR: do not use assignment in if condition
#55: FILE: tools/testing/selftests/bpf/test_loader.c:594:
+		} else if ((val = str_has_pfx(s, "test_btf_func_path="))) {

WARNING: line length of 84 exceeds 80 columns
#125: FILE: tools/testing/selftests/bpf/test_loader.c:1205:
+			cname = btf__name_by_offset(custom_btf, custom_t->name_off);

WARNING: line length of 84 exceeds 80 columns
#150: FILE: tools/testing/selftests/bpf/test_loader.c:1230:
+		/* Add a new FUNC_PROTO: param names from custom, types from prog */

WARNING: line length of 91 exceeds 80 columns
#162: FILE: tools/testing/selftests/bpf/test_loader.c:1242:
+			pname = btf__name_by_offset(custom_btf, custom_params[j].name_off);

WARNING: line length of 94 exceeds 80 columns
#163: FILE: tools/testing/selftests/bpf/test_loader.c:1243:
+			err = btf__add_func_param(prog_btf, pname ?: "", prog_param_types[j]);

WARNING: line length of 87 exceeds 80 columns
#174: FILE: tools/testing/selftests/bpf/test_loader.c:1254:
+		((struct btf_type *)btf__type_by_id(prog_btf, i))->type = new_proto_id;

WARNING: line length of 84 exceeds 80 columns
#190: FILE: tools/testing/selftests/bpf/test_loader.c:1318:
+	 * btf_custom_func_path also serves as btf_custom_path for kfunc resolution.

total: 1 errors, 6 warnings, 0 checks, 173 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 87ee8814e2ca ("selftests/bpf: Add BTF fixup for __naked subprog parameter names") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE FILE_PATH_CHANGES GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.