==========
checkpatch - FAILED

WARNING: line length of 88 exceeds 80 columns
#55: FILE: tools/lib/bpf/libbpf.c:14186:
+		pr_warn("failed to create AF_ALG socket for SHA256: %s\n", errstr(err));

WARNING: line length of 89 exceeds 80 columns
#61: FILE: tools/lib/bpf/libbpf.c:14192:
+		pr_warn("failed to bind to AF_ALG socket for SHA256: %s\n", errstr(err));

WARNING: line length of 93 exceeds 80 columns
#68: FILE: tools/lib/bpf/libbpf.c:14199:
+		pr_warn("failed to accept from AF_ALG socket for SHA256: %s\n", errstr(err));

WARNING: line length of 95 exceeds 80 columns
#74: FILE: tools/lib/bpf/libbpf.c:14205:
+		pr_warn("failed to write data to AF_ALG socket for SHA256: %s\n", errstr(err));

WARNING: line length of 81 exceeds 80 columns
#78: FILE: tools/lib/bpf/libbpf.c:14209:
+	if (read(op_fd, sha_out, SHA256_DIGEST_LENGTH) != SHA256_DIGEST_LENGTH) {

WARNING: line length of 87 exceeds 80 columns
#80: FILE: tools/lib/bpf/libbpf.c:14211:
+		pr_warn("failed to read SHA256 from AF_ALG socket: %s\n", errstr(err));

ERROR: Macros with complex values should be enclosed in parentheses
#103: FILE: tools/lib/bpf/libbpf_internal.h:744:
+#define SHA256_DWORD_SIZE SHA256_DIGEST_LENGTH / sizeof(__u64)

BUT SEE:

   do {} while (0) advice is over-stated in a few situations:

   The more obvious case is macros, like MODULE_PARM_DESC, invoked at
   file-scope, where C disallows code (it must be in functions).  See
   $exceptions if you have one to add by name.

   More troublesome is declarative macros used at top of new scope,
   like DECLARE_PER_CPU.  These might just compile with a do-while-0
   wrapper, but would be incorrect.  Most of these are handled by
   detecting struct,union,etc declaration primitives in $exceptions.

   Theres also macros called inside an if (block), which "return" an
   expression.  These cannot do-while, and need a ({}) wrapper.

   Enjoy this qualification while we work to improve our heuristics.

total: 1 errors, 6 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 63e947223f71 ("libbpf: Implement SHA256 internal helper") 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.