Hi Xin,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Xin-Long/sctp-Implement-RFC6951-UDP-Encapsulation-of-SCTP/20201008-175211
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 9faebeb2d80065926dfbc09cb73b1bb7779a89cd
config: i386-randconfig-s002-20201008 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.2-218-gc0e96d6d-dirty
        # https://github.com/0day-ci/linux/commit/9119d2be86deb6950b26b152a51ddad0a95182a5
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Xin-Long/sctp-Implement-RFC6951-UDP-Encapsulation-of-SCTP/20201008-175211
        git checkout 9119d2be86deb6950b26b152a51ddad0a95182a5
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

echo
echo "sparse warnings: (new ones prefixed by >>)"
echo
   net/sctp/sm_make_chunk.c: note: in included file (through include/net/sctp/sctp.h):
   include/net/sctp/structs.h:334:41: sparse: sparse: array of flexible structures
>> net/sctp/sm_make_chunk.c:1157:24: sparse: sparse: cast from restricted __be16
>> net/sctp/sm_make_chunk.c:1157:24: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned short [usertype] val @@     got restricted __be16 [usertype] encap_port @@
>> net/sctp/sm_make_chunk.c:1157:24: sparse:     expected unsigned short [usertype] val
>> net/sctp/sm_make_chunk.c:1157:24: sparse:     got restricted __be16 [usertype] encap_port
>> net/sctp/sm_make_chunk.c:1157:24: sparse: sparse: cast from restricted __be16
>> net/sctp/sm_make_chunk.c:1157:24: sparse: sparse: cast from restricted __be16
   net/sctp/sm_make_chunk.c:1158:24: sparse: sparse: cast from restricted __be16
   net/sctp/sm_make_chunk.c:1158:24: sparse: sparse: incorrect type in argument 1 (different base types) @@     expected unsigned short [usertype] val @@     got restricted __be16 [usertype] encap_port @@
   net/sctp/sm_make_chunk.c:1158:24: sparse:     expected unsigned short [usertype] val
   net/sctp/sm_make_chunk.c:1158:24: sparse:     got restricted __be16 [usertype] encap_port
   net/sctp/sm_make_chunk.c:1158:24: sparse: sparse: cast from restricted __be16
   net/sctp/sm_make_chunk.c:1158:24: sparse: sparse: cast from restricted __be16
   net/sctp/sm_make_chunk.c:3081:48: sparse: sparse: incorrect type in argument 2 (different base types) @@     expected int optname @@     got restricted __be16 @@
   net/sctp/sm_make_chunk.c:3081:48: sparse:     expected int optname
   net/sctp/sm_make_chunk.c:3081:48: sparse:     got restricted __be16
   net/sctp/sm_make_chunk.c:3153:48: sparse: sparse: incorrect type in argument 2 (different base types) @@     expected int optname @@     got restricted __be16 @@
   net/sctp/sm_make_chunk.c:3153:48: sparse:     expected int optname
   net/sctp/sm_make_chunk.c:3153:48: sparse:     got restricted __be16

vim +1157 net/sctp/sm_make_chunk.c

  1144	
  1145	struct sctp_chunk *sctp_make_new_encap_port(const struct sctp_association *asoc,
  1146						    const struct sctp_chunk *chunk)
  1147	{
  1148		struct sctp_new_encap_port_hdr nep;
  1149		struct sctp_chunk *retval;
  1150	
  1151		retval = sctp_make_abort(asoc, chunk,
  1152					 sizeof(struct sctp_errhdr) + sizeof(nep));
  1153		if (!retval)
  1154			goto nodata;
  1155	
  1156		sctp_init_cause(retval, SCTP_ERROR_NEW_ENCAP_PORT, sizeof(nep));
> 1157		nep.cur_port = htons(SCTP_INPUT_CB(chunk->skb)->encap_port);
  1158		nep.new_port = htons(chunk->transport->encap_port);
  1159		sctp_addto_chunk(retval, sizeof(nep), &nep);
  1160	
  1161	nodata:
  1162		return retval;
  1163	}
  1164	

---
0-DAY CI Kernel Test Service, Intel Corporation
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