arch/x86/mm/pgtable.c:600: warning: Function parameter or member 'p4d' not described in 'p4d_set_huge'

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

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   f2e8a57ee9036c7d5443382b6c3c09b51a92ec7e
commit: b8504058a06bd19286c8b59539eebfda69d1ecb5 x86/mm: Add basic defines/helpers for CONFIG_X86_5LEVEL=y
date:   7 years ago
config: i386-allnoconfig (https://download.01.org/0day-ci/archive/20231209/202312092055.UWtOrFJM-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231209/202312092055.UWtOrFJM-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/oe-kbuild-all/202312092055.UWtOrFJM-lkp@intel.com/

All warnings (new ones prefixed by >>):

   arch/x86/mm/pgtable.c: In function 'pgd_alloc':
   arch/x86/mm/pgtable.c:380:13: warning: 'preallocate_pmds' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
     380 |         if (preallocate_pmds(mm, pmds) != 0)
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/x86/mm/pgtable.c:380:13: note: referencing argument 2 of type 'pmd_t *[0]'
   arch/x86/mm/pgtable.c:214:12: note: in a call to function 'preallocate_pmds'
     214 | static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[])
         |            ^~~~~~~~~~~~~~~~
   arch/x86/mm/pgtable.c:401:9: warning: 'free_pmds' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
     401 |         free_pmds(mm, pmds);
         |         ^~~~~~~~~~~~~~~~~~~
   arch/x86/mm/pgtable.c:401:9: note: referencing argument 2 of type 'pmd_t *[0]'
   arch/x86/mm/pgtable.c:202:13: note: in a call to function 'free_pmds'
     202 | static void free_pmds(struct mm_struct *mm, pmd_t *pmds[])
         |             ^~~~~~~~~
   arch/x86/mm/pgtable.c:394:9: warning: 'pgd_prepopulate_pmd' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=]
     394 |         pgd_prepopulate_pmd(mm, pgd, pmds);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/x86/mm/pgtable.c:394:9: note: referencing argument 3 of type 'pmd_t *[0]'
   arch/x86/mm/pgtable.c:270:13: note: in a call to function 'pgd_prepopulate_pmd'
     270 | static void pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmds[])
         |             ^~~~~~~~~~~~~~~~~~~
   arch/x86/include/asm/bitops.h: Assembler messages:
   arch/x86/include/asm/bitops.h:265: Warning: no instruction mnemonic suffix given and no register operands; using default for `btr'
   arch/x86/include/asm/bitops.h:265: Warning: no instruction mnemonic suffix given and no register operands; using default for `btr'
   arch/x86/mm/pgtable.c:563: warning: Function parameter or member 'reserve' not described in 'reserve_top_address'
>> arch/x86/mm/pgtable.c:600: warning: Function parameter or member 'p4d' not described in 'p4d_set_huge'
>> arch/x86/mm/pgtable.c:600: warning: Function parameter or member 'addr' not described in 'p4d_set_huge'
>> arch/x86/mm/pgtable.c:600: warning: Function parameter or member 'prot' not described in 'p4d_set_huge'
>> arch/x86/mm/pgtable.c:610: warning: Function parameter or member 'p4d' not described in 'p4d_clear_huge'
   arch/x86/mm/pgtable.c:634: warning: Function parameter or member 'pud' not described in 'pud_set_huge'
   arch/x86/mm/pgtable.c:634: warning: Function parameter or member 'addr' not described in 'pud_set_huge'
   arch/x86/mm/pgtable.c:634: warning: Function parameter or member 'prot' not described in 'pud_set_huge'
   arch/x86/mm/pgtable.c:659: warning: Function parameter or member 'pmd' not described in 'pmd_set_huge'
   arch/x86/mm/pgtable.c:659: warning: Function parameter or member 'addr' not described in 'pmd_set_huge'
   arch/x86/mm/pgtable.c:659: warning: Function parameter or member 'prot' not described in 'pmd_set_huge'
   arch/x86/mm/pgtable.c:685: warning: Function parameter or member 'pud' not described in 'pud_clear_huge'
   arch/x86/mm/pgtable.c:700: warning: Function parameter or member 'pmd' not described in 'pmd_clear_huge'


vim +600 arch/x86/mm/pgtable.c

   591	
   592	#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
   593	#ifdef CONFIG_X86_5LEVEL
   594	/**
   595	 * p4d_set_huge - setup kernel P4D mapping
   596	 *
   597	 * No 512GB pages yet -- always return 0
   598	 */
   599	int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
 > 600	{
   601		return 0;
   602	}
   603	
   604	/**
   605	 * p4d_clear_huge - clear kernel P4D mapping when it is set
   606	 *
   607	 * No 512GB pages yet -- always return 0
   608	 */
   609	int p4d_clear_huge(p4d_t *p4d)
 > 610	{
   611		return 0;
   612	}
   613	#endif
   614	

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