Re: [RFC V1 PATCH mm-hotfixes 3/3] x86/mm: convert {pgd,p4d}_populate{,_init} to _kernel variant

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

Hi Harry,

[This is a private test report for your RFC patch.]
kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]

url:    https://github.com/intel-lab-lkp/linux/commits/Harry-Yoo/mm-introduce-and-use-pgd-p4d-_populate_kernel/20250709-211850
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20250709131657.5660-4-harry.yoo%40oracle.com
patch subject: [RFC V1 PATCH mm-hotfixes 3/3] x86/mm: convert {pgd,p4d}_populate{,_init} to _kernel variant
config: x86_64-buildonly-randconfig-001-20250710 (https://download.01.org/0day-ci/archive/20250710/202507101816.sVROo3Mj-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250710/202507101816.sVROo3Mj-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/202507101816.sVROo3Mj-lkp@intel.com/

All warnings (new ones prefixed by >>):

   arch/x86/mm/init_64.c: In function '__kernel_physical_mapping_init':
>> arch/x86/mm/init_64.c:735:30: warning: variable 'vaddr_start' set but not used [-Wunused-but-set-variable]
     735 |         unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
         |                              ^~~~~~~~~~~


vim +/vaddr_start +735 arch/x86/mm/init_64.c

7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  728  
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  729  static unsigned long __meminit
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  730  __kernel_physical_mapping_init(unsigned long paddr_start,
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  731  			       unsigned long paddr_end,
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  732  			       unsigned long page_size_mask,
c164fbb40c43f8 arch/x86/mm/init_64.c Logan Gunthorpe     2020-04-10  733  			       pgprot_t prot, bool init)
^1da177e4c3f41 arch/x86_64/mm/init.c Linus Torvalds      2005-04-16  734  {
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21 @735  	unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
^1da177e4c3f41 arch/x86_64/mm/init.c Linus Torvalds      2005-04-16  736  
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  737  	paddr_last = paddr_end;
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  738  	vaddr = (unsigned long)__va(paddr_start);
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  739  	vaddr_end = (unsigned long)__va(paddr_end);
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  740  	vaddr_start = vaddr;
^1da177e4c3f41 arch/x86_64/mm/init.c Linus Torvalds      2005-04-16  741  
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  742  	for (; vaddr < vaddr_end; vaddr = vaddr_next) {
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  743  		pgd_t *pgd = pgd_offset_k(vaddr);
f2a6a7050109e0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-03-17  744  		p4d_t *p4d;
44df75e629106e arch/x86_64/mm/init.c Matt Tolentino      2006-01-17  745  
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  746  		vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
4f9c11dd49fb73 arch/x86/mm/init_64.c Jeremy Fitzhardinge 2008-06-25  747  
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  748  		if (pgd_val(*pgd)) {
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  749  			p4d = (p4d_t *)pgd_page_vaddr(*pgd);
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  750  			paddr_last = phys_p4d_init(p4d, __pa(vaddr),
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  751  						   __pa(vaddr_end),
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  752  						   page_size_mask,
c164fbb40c43f8 arch/x86/mm/init_64.c Logan Gunthorpe     2020-04-10  753  						   prot, init);
4f9c11dd49fb73 arch/x86/mm/init_64.c Jeremy Fitzhardinge 2008-06-25  754  			continue;
4f9c11dd49fb73 arch/x86/mm/init_64.c Jeremy Fitzhardinge 2008-06-25  755  		}
4f9c11dd49fb73 arch/x86/mm/init_64.c Jeremy Fitzhardinge 2008-06-25  756  
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  757  		p4d = alloc_low_page();
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  758  		paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
c164fbb40c43f8 arch/x86/mm/init_64.c Logan Gunthorpe     2020-04-10  759  					   page_size_mask, prot, init);
8ae3a5a8dff2c9 arch/x86/mm/init_64.c Jan Beulich         2008-08-21  760  
8ae3a5a8dff2c9 arch/x86/mm/init_64.c Jan Beulich         2008-08-21  761  		spin_lock(&init_mm.page_table_lock);
ed7588d5dc6f5e arch/x86/mm/init_64.c Kirill A. Shutemov  2018-05-18  762  		if (pgtable_l5_enabled())
f7dd285ef7a44b arch/x86/mm/init_64.c Harry Yoo           2025-07-09  763  			pgd_populate_kernel_init(vaddr, pgd, p4d, init);
7e82ea946ae4d0 arch/x86/mm/init_64.c Kirill A. Shutemov  2017-06-06  764  		else
f7dd285ef7a44b arch/x86/mm/init_64.c Harry Yoo           2025-07-09  765  			p4d_populate_kernel_init(vaddr, p4d_offset(pgd, vaddr),
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  766  						 (pud_t *) p4d, init);
eccd906484d1cd arch/x86/mm/init_64.c Brijesh Singh       2019-04-17  767  
8ae3a5a8dff2c9 arch/x86/mm/init_64.c Jan Beulich         2008-08-21  768  		spin_unlock(&init_mm.page_table_lock);
^1da177e4c3f41 arch/x86_64/mm/init.c Linus Torvalds      2005-04-16  769  	}
9b861528a8012e arch/x86/mm/init_64.c Haicheng Li         2010-08-20  770  
59b3d0206d74a7 arch/x86/mm/init_64.c Thomas Garnier      2016-06-21  771  	return paddr_last;
b50efd2a55fc13 arch/x86/mm/init_64.c Yinghai Lu          2008-07-08  772  }
7b16eb8930d1e2 arch/x86/mm/init_64.c Yinghai Lu          2008-07-09  773  

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