tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   4b6c093e21d36bede0fd88fd0aeb3b03647260e4
commit: 670d0a4b10704667765f7d18f7592993d02783aa sparse: use identifiers to define address spaces
date:   8 weeks ago
config: xtensa-randconfig-s032-20200816 (attached as .config)
compiler: xtensa-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.2-180-g49f7e13a-dirty
        git checkout 670d0a4b10704667765f7d18f7592993d02783aa
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=xtensa 

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


sparse warnings: (new ones prefixed by >>)

   net/netfilter/nf_conntrack_netlink.c:1962:34: sparse: sparse: incompatible types in comparison expression (different address spaces):
   net/netfilter/nf_conntrack_netlink.c:1962:34: sparse:    struct nf_conntrack_helper [noderef] __rcu *
   net/netfilter/nf_conntrack_netlink.c:1962:34: sparse:    struct nf_conntrack_helper *
>> net/netfilter/nf_conntrack_netlink.c:3414:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected char const *__cs @@     got char [noderef] __rcu * @@
   net/netfilter/nf_conntrack_netlink.c:3414:29: sparse:     expected char const *__cs
   net/netfilter/nf_conntrack_netlink.c:3414:29: sparse:     got char [noderef] __rcu *
   net/netfilter/nf_conntrack_netlink.c: note: in included file (through include/linux/seqlock.h, include/linux/time.h, include/linux/stat.h, ...):
   include/linux/spinlock.h:393:9: sparse: sparse: context imbalance in 'ctnetlink_dump_table' - unexpected unlock

# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=670d0a4b10704667765f7d18f7592993d02783aa
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 670d0a4b10704667765f7d18f7592993d02783aa
vim +3414 net/netfilter/nf_conntrack_netlink.c

c1d10adb4a521d Pablo Neira Ayuso 2006-01-05  3406  
ac7b848390036d Florian Westphal  2017-07-26  3407  static bool expect_iter_name(struct nf_conntrack_expect *exp, void *data)
ac7b848390036d Florian Westphal  2017-07-26  3408  {
ac7b848390036d Florian Westphal  2017-07-26  3409  	const struct nf_conn_help *m_help;
ac7b848390036d Florian Westphal  2017-07-26  3410  	const char *name = data;
ac7b848390036d Florian Westphal  2017-07-26  3411  
ac7b848390036d Florian Westphal  2017-07-26  3412  	m_help = nfct_help(exp->master);
ac7b848390036d Florian Westphal  2017-07-26  3413  
ac7b848390036d Florian Westphal  2017-07-26 @3414  	return strcmp(m_help->helper->name, name) == 0;
ac7b848390036d Florian Westphal  2017-07-26  3415  }
ac7b848390036d Florian Westphal  2017-07-26  3416  

:::::: The code at line 3414 was first introduced by commit
:::::: ac7b848390036dadd4351899d2a23748075916bd netfilter: expect: add and use nf_ct_expect_iterate helpers

:::::: TO: Florian Westphal <fw@strlen.de>
:::::: CC: Pablo Neira Ayuso <pablo@netfilter.org>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org