Re: [PATCH v5 01/21] [draft] net/tcp: Prepare tcp_md5sig_pool for TCP-AO

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

Hi Dmitry,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 7e364e56293bb98cae1b55fd835f5991c4e96e7d]

url:    https://github.com/intel-lab-lkp/linux/commits/Dmitry-Safonov/net-tcp-Prepare-tcp_md5sig_pool-for-TCP-AO/20230404-054020
base:   7e364e56293bb98cae1b55fd835f5991c4e96e7d
patch link:    https://lore.kernel.org/r/20230403213420.1576559-2-dima%40arista.com
patch subject: [PATCH v5 01/21] [draft] net/tcp: Prepare tcp_md5sig_pool for TCP-AO
config: i386-randconfig-a001-20230403 (https://download.01.org/0day-ci/archive/20230404/202304040916.I3rkyzLG-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/94408bb4cf5cbcc772ab4d70eeb73bda183c6124
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Dmitry-Safonov/net-tcp-Prepare-tcp_md5sig_pool-for-TCP-AO/20230404-054020
        git checkout 94408bb4cf5cbcc772ab4d70eeb73bda183c6124
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/ipv4/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304040916.I3rkyzLG-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> net/ipv4/tcp_sigpool.c:63:9: warning: comparison of distinct pointer types ('typeof (size) *' (aka 'unsigned int *') and 'typeof (__scratch_size) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types]
           size = max(size, __scratch_size);
                  ^~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/minmax.h:74:19: note: expanded from macro 'max'
   #define max(x, y)       __careful_cmp(x, y, >)
                           ^~~~~~~~~~~~~~~~~~~~~~
   include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
           __builtin_choose_expr(__safe_cmp(x, y), \
                                 ^~~~~~~~~~~~~~~~
   include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
                   (__typecheck(x, y) && __no_side_effects(x, y))
                    ^~~~~~~~~~~~~~~~~
   include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
           (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
                      ~~~~~~~~~~~~~~ ^  ~~~~~~~~~~~~~~
   1 warning generated.


vim +63 net/ipv4/tcp_sigpool.c

    43	
    44	/*
    45	 * sigpool_reserve_scratch - re-allocates scratch buffer, slow-path
    46	 * @size: request size for the scratch/temp buffer
    47	 */
    48	static int sigpool_reserve_scratch(size_t size)
    49	{
    50		struct scratches_to_free *stf;
    51		size_t stf_sz = struct_size(stf, scratches, num_possible_cpus());
    52		int cpu, err = 0;
    53	
    54		lockdep_assert_held(&cpool_mutex);
    55		if (__scratch_size >= size)
    56			return 0;
    57	
    58		stf = kmalloc(stf_sz, GFP_KERNEL);
    59		if (!stf)
    60			return -ENOMEM;
    61		stf->cnt = 0;
    62	
  > 63		size = max(size, __scratch_size);
    64		cpus_read_lock();
    65		for_each_possible_cpu(cpu) {
    66			void *scratch, *old_scratch;
    67	
    68			scratch = kmalloc_node(size, GFP_KERNEL, cpu_to_node(cpu));
    69			if (!scratch) {
    70				err = -ENOMEM;
    71				break;
    72			}
    73	
    74			old_scratch = rcu_replace_pointer(per_cpu(sigpool_scratch, cpu), scratch, lockdep_is_held(&cpool_mutex));
    75			if (!cpu_online(cpu) || !old_scratch) {
    76				kfree(old_scratch);
    77				continue;
    78			}
    79			stf->scratches[stf->cnt++] = old_scratch;
    80		}
    81		cpus_read_unlock();
    82		if (!err)
    83			__scratch_size = size;
    84	
    85		call_rcu(&stf->rcu, free_old_scratches);
    86		return err;
    87	}
    88	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests