WARNING: else is not generally useful after a break or return
#325: FILE: include/net/tcp.h:2442:
+		return rto_time_stamp_us - tcp_sk(sk)->tcp_mstamp;
+	} else {

CHECK: Alignment should match open parenthesis
#327: FILE: include/net/tcp.h:2444:
+		WARN_ONCE(1,
+			"rtx queue emtpy: inflight %u tlp_high_seq %u state %u\n",

WARNING: line length of 89 exceeds 80 columns
#328: FILE: include/net/tcp.h:2445:
+			tcp_sk(sk)->packets_out, tcp_sk(sk)->tlp_high_seq, sk->sk_state);

WARNING: The commit message has 'Call Trace:', perhaps it also needs a 'Fixes:' tag?

total: 0 errors, 3 warnings, 1 checks, 22 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 411a8b37679c ("tcp: check skb is non-NULL in tcp_rto_delta_us()") 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, 1 checks, 22 lines checked