Re: [PATCH v3 net-next 08/15] net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously

[kbuild test robot <lkp@intel.com>]

Hi Vladimir,

I love your patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]
[also build test WARNING on next-20200512]
[cannot apply to linus/master v5.7-rc5]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Vladimir-Oltean/Traffic-support-for-dsa_8021q-in-vlan_filtering-1-mode/20200513-012422
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 3242956bd610af40e884b530b6c6f76f5bf85f3b
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.1-191-gc51a0382-dirty
        make ARCH=x86_64 allmodconfig
        make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'

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


sparse warnings: (new ones prefixed by >>)

>> net/dsa/tag_sja1105.c:76:34: sparse: sparse: cast to restricted __be16
>> net/dsa/tag_sja1105.c:76:34: sparse: sparse: cast to restricted __be16
>> net/dsa/tag_sja1105.c:76:34: sparse: sparse: cast to restricted __be16
>> net/dsa/tag_sja1105.c:76:34: sparse: sparse: cast to restricted __be16
>> net/dsa/tag_sja1105.c:76:16: sparse: sparse: restricted __be16 degrades to integer
   net/dsa/tag_sja1105.c:79:34: sparse: sparse: cast to restricted __be16
   net/dsa/tag_sja1105.c:79:34: sparse: sparse: cast to restricted __be16
   net/dsa/tag_sja1105.c:79:34: sparse: sparse: cast to restricted __be16
   net/dsa/tag_sja1105.c:79:34: sparse: sparse: cast to restricted __be16
   net/dsa/tag_sja1105.c:79:16: sparse: sparse: restricted __be16 degrades to integer

vim +76 net/dsa/tag_sja1105.c

    71	
    72	static bool sja1105_can_use_vlan_as_tags(const struct sk_buff *skb)
    73	{
    74		struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
    75	
  > 76		if (hdr->h_vlan_proto == ntohs(ETH_P_SJA1105))
    77			return true;
    78	
    79		if (hdr->h_vlan_proto != ntohs(ETH_P_8021Q))
    80			return false;
    81	
    82		return vid_is_dsa_8021q(ntohs(hdr->h_vlan_TCI) & VLAN_VID_MASK);
    83	}
    84	

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