Warnings before patch:
files: ['Documentation/networking/ip-sysctl.rst', 'net/ipv4/sysctl_net_ipv4.c', 'net/ipv4/tcp_input.c', 'include/linux/tcp.h', 'net/ipv4/tcp_output.c', 'include/net/tcp_ecn.h']
<parse fail>: Warning: include/linux/tcp.h:59 No description found for return value of 'skb_tcp_all_headers'
<parse fail>: Warning: include/linux/tcp.h:74 No description found for return value of 'skb_inner_tcp_all_headers'
<parse fail>: Warning: net/ipv4/tcp_input.c:5001 No description found for return value of 'tcp_try_coalesce'
<parse fail>: Warning: net/ipv4/tcp_output.c:3907 No description found for return value of 'tcp_make_synack'
Warning: include/linux/tcp.h:59 No description found for return value of 'skb_tcp_all_headers'
Warning: include/linux/tcp.h:74 No description found for return value of 'skb_inner_tcp_all_headers'
Warning: net/ipv4/tcp_input.c:5001 No description found for return value of 'tcp_try_coalesce'
Warning: net/ipv4/tcp_output.c:3907 No description found for return value of 'tcp_make_synack'

Current warnings:
files: ['Documentation/networking/ip-sysctl.rst', 'net/ipv4/sysctl_net_ipv4.c', 'net/ipv4/tcp_input.c', 'include/linux/tcp.h', 'net/ipv4/tcp_output.c', 'include/net/tcp_ecn.h']
<parse fail>: Warning: include/linux/tcp.h:59 No description found for return value of 'skb_tcp_all_headers'
<parse fail>: Warning: include/linux/tcp.h:74 No description found for return value of 'skb_inner_tcp_all_headers'
<parse fail>: Warning: net/ipv4/tcp_input.c:5011 No description found for return value of 'tcp_try_coalesce'
<parse fail>: Warning: net/ipv4/tcp_output.c:3912 No description found for return value of 'tcp_make_synack'
Warning: include/linux/tcp.h:59 No description found for return value of 'skb_tcp_all_headers'
Warning: include/linux/tcp.h:74 No description found for return value of 'skb_inner_tcp_all_headers'
Warning: net/ipv4/tcp_input.c:5011 No description found for return value of 'tcp_try_coalesce'
Warning: net/ipv4/tcp_output.c:3912 No description found for return value of 'tcp_make_synack'

Warnings before: 4 after: 4