arch/sparc/include/asm/string.h:15:25: warning: '__builtin_memcpy' forming offset [5, 8] is out of the bounds [0, 4] of object 'k' with type 'long unsigned int'

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

:::::: 
:::::: Manual check reason: "bisect to a FBC not belonging to original linux-review patches: branch: linux-review/T-J-Mercier/bpf-htab-Split-htab_elem_lru-and-htab_elem_pcpu-off-of-htab_elem/20261002-091734, commit: ff6cf05dbbb8d27bf0e53e860d6320dd75ab8f78"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
TO: "T.J. Mercier" <tjmercier@google.com>
CC: 0day robot <lkp@intel.com>

tree:   https://github.com/intel-lab-lkp/linux/commits/T-J-Mercier/bpf-htab-Split-htab_elem_lru-and-htab_elem_pcpu-off-of-htab_elem/20261002-091734
head:   ff6cf05dbbb8d27bf0e53e860d6320dd75ab8f78
commit: ff6cf05dbbb8d27bf0e53e860d6320dd75ab8f78 bpf: htab: Reduce elem_size by 8 bytes for small key sizes
date:   12 hours ago
:::::: branch date: 12 hours ago
:::::: commit date: 12 hours ago
config: sparc-randconfig-1000-20261003 (https://download.01.org/0day-ci/archive/20261003/202610031215.ybqsLvSp-lkp@intel.com/config)
compiler: sparc-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261003/202610031215.ybqsLvSp-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202610031215.ybqsLvSp-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/string.h:65,
                    from include/linux/bitmap.h:13,
                    from include/linux/cpumask.h:11,
                    from arch/sparc/include/asm/smp_32.h:15,
                    from arch/sparc/include/asm/smp.h:7,
                    from arch/sparc/include/asm/switch_to_32.h:5,
                    from arch/sparc/include/asm/switch_to.h:7,
                    from arch/sparc/include/asm/ptrace.h:120,
                    from arch/sparc/include/asm/thread_info_32.h:19,
                    from arch/sparc/include/asm/thread_info.h:7,
                    from include/linux/thread_info.h:62,
                    from include/asm-generic/preempt.h:5,
                    from ./arch/sparc/include/generated/asm/preempt.h:1,
                    from include/linux/preempt.h:107,
                    from include/linux/alloc_tag.h:11,
                    from include/linux/workqueue.h:9,
                    from include/linux/bpf.h:12,
                    from kernel/bpf/hashtab.c:5:
   In function '__lookup_elem_raw',
       inlined from 'lookup_nulls_elem_raw' at kernel/bpf/hashtab.c:843:6,
       inlined from '__htab_lookup' at kernel/bpf/hashtab.c:866:6,
       inlined from '__htab_map_lookup_elem_u64' at kernel/bpf/hashtab.c:890:9:
>> arch/sparc/include/asm/string.h:15:25: warning: '__builtin_memcpy' forming offset [5, 8] is out of the bounds [0, 4] of object 'k' with type 'long unsigned int' [-Warray-bounds]
    #define memcpy(t, f, n) __builtin_memcpy(t, f, n)
                            ^~~~~~~~~~~~~~~~~~~~~~~~~
   kernel/bpf/hashtab.c:812:3: note: in expansion of macro 'memcpy'
      memcpy(&k, key, key_size);
      ^~~~~~
   kernel/bpf/hashtab.c: In function '__htab_map_lookup_elem_u64':
   kernel/bpf/hashtab.c:810:17: note: 'k' declared here
      unsigned long k = 0;
                    ^


vim +15 arch/sparc/include/asm/string.h

70a6fcf3283a0a Al Viro 2016-01-17  13  
70a6fcf3283a0a Al Viro 2016-01-17  14  #define __HAVE_ARCH_MEMCPY
70a6fcf3283a0a Al Viro 2016-01-17 @15  #define memcpy(t, f, n) __builtin_memcpy(t, f, n)
70a6fcf3283a0a Al Viro 2016-01-17  16  

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