WARNING: externs should be avoided in .c files
#79: FILE: tools/testing/selftests/bpf/progs/test_global_map_resize.c:42:
+extern int LINUX_KERNEL_VERSION __kconfig;

total: 0 errors, 1 warnings, 0 checks, 63 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 84e87592ebdd ("libbpf: fix possible use-after-free for externs") 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, 1 warnings, 0 checks, 63 lines checked