WARNING: ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP
#24: FILE: tools/lib/bpf/str_error.c:8:
+#ifndef ENOTSUPP

WARNING: ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP
#25: FILE: tools/lib/bpf/str_error.c:9:
+#define ENOTSUPP	524

WARNING: ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP
#59: FILE: tools/lib/bpf/str_error.c:62:
+	case -ENOTSUPP: return "-ENOTSUPP";

total: 0 errors, 3 warnings, 0 checks, 79 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 1b62fe74d924 ("libbpf: introduce errstr() for stringifying errno") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE 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.
total: 0 errors, 3 warnings, 0 checks, 79 lines checked