WARNING: line length of 88 exceeds 80 columns
#61: FILE: net/ipv4/ip_gre.c:195:
+			data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */

WARNING: line length of 81 exceeds 80 columns
#63: FILE: net/ipv4/ip_gre.c:197:
+		if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,

total: 0 errors, 2 warnings, 0 checks, 34 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 7fed2b835c45 ("ipv4: ip_gre: Fix set but not used warning in ipgre_err() if IPv4-only") 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, 2 warnings, 0 checks, 34 lines checked