[android-common:android12-5.4 5/5] mm/memory.c:1807:22: warning: variable 'mapped_pte' set but not used

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

:::::: 
:::::: Manual check reason: "low confidence bisect report"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
TO: cros-kernel-buildreports@googlegroups.com

tree:   https://android.googlesource.com/kernel/common android12-5.4
head:   7055541caeda53d6275f23b878618d609132e955
commit: 67a982ee20d20e112f15eff98592a718de7c652e [5/5] mm/memory.c: fix potential pte_unmap_unlock pte error
:::::: branch date: 14 hours ago
:::::: commit date: 4 years, 9 months ago
config: i386-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20251125/202511250100.9VNeAX9M-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511250100.9VNeAX9M-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/202511250100.9VNeAX9M-lkp@intel.com/

All warnings (new ones prefixed by >>):

   mm/memory.c: In function 'copy_pte_range':
   mm/memory.c:800:31: warning: variable 'orig_dst_pte' set but not used [-Wunused-but-set-variable]
     800 |         pte_t *orig_src_pte, *orig_dst_pte;
         |                               ^~~~~~~~~~~~
   mm/memory.c:800:16: warning: variable 'orig_src_pte' set but not used [-Wunused-but-set-variable]
     800 |         pte_t *orig_src_pte, *orig_dst_pte;
         |                ^~~~~~~~~~~~
   mm/memory.c: In function 'remap_pte_range':
>> mm/memory.c:1807:22: warning: variable 'mapped_pte' set but not used [-Wunused-but-set-variable]
    1807 |         pte_t *pte, *mapped_pte;
         |                      ^~~~~~~~~~


vim +/mapped_pte +1807 mm/memory.c

b2770da6425406 Ross Zwisler   2017-09-06  1797  
^1da177e4c3f41 Linus Torvalds 2005-04-16  1798  /*
^1da177e4c3f41 Linus Torvalds 2005-04-16  1799   * maps a range of physical memory into the requested pages. the old
^1da177e4c3f41 Linus Torvalds 2005-04-16  1800   * mappings are removed. any references to nonexistent pages results
^1da177e4c3f41 Linus Torvalds 2005-04-16  1801   * in null mappings (currently treated as "copy-on-access")
^1da177e4c3f41 Linus Torvalds 2005-04-16  1802   */
^1da177e4c3f41 Linus Torvalds 2005-04-16  1803  static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd,
^1da177e4c3f41 Linus Torvalds 2005-04-16  1804  			unsigned long addr, unsigned long end,
^1da177e4c3f41 Linus Torvalds 2005-04-16  1805  			unsigned long pfn, pgprot_t prot)
^1da177e4c3f41 Linus Torvalds 2005-04-16  1806  {
67a982ee20d20e Miaohe Lin     2021-02-24 @1807  	pte_t *pte, *mapped_pte;
c74df32c724a16 Hugh Dickins   2005-10-29  1808  	spinlock_t *ptl;
42e4089c789072 Andi Kleen     2018-06-13  1809  	int err = 0;
^1da177e4c3f41 Linus Torvalds 2005-04-16  1810  
67a982ee20d20e Miaohe Lin     2021-02-24  1811  	mapped_pte = pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
^1da177e4c3f41 Linus Torvalds 2005-04-16  1812  	if (!pte)
^1da177e4c3f41 Linus Torvalds 2005-04-16  1813  		return -ENOMEM;
6606c3e0da5360 Zachary Amsden 2006-09-30  1814  	arch_enter_lazy_mmu_mode();
^1da177e4c3f41 Linus Torvalds 2005-04-16  1815  	do {
^1da177e4c3f41 Linus Torvalds 2005-04-16  1816  		BUG_ON(!pte_none(*pte));
42e4089c789072 Andi Kleen     2018-06-13  1817  		if (!pfn_modify_allowed(pfn, prot)) {
42e4089c789072 Andi Kleen     2018-06-13  1818  			err = -EACCES;
42e4089c789072 Andi Kleen     2018-06-13  1819  			break;
42e4089c789072 Andi Kleen     2018-06-13  1820  		}
7e675137a8e1a4 Nick Piggin    2008-04-28  1821  		set_pte_at(mm, addr, pte, pte_mkspecial(pfn_pte(pfn, prot)));
^1da177e4c3f41 Linus Torvalds 2005-04-16  1822  		pfn++;
^1da177e4c3f41 Linus Torvalds 2005-04-16  1823  	} while (pte++, addr += PAGE_SIZE, addr != end);
6606c3e0da5360 Zachary Amsden 2006-09-30  1824  	arch_leave_lazy_mmu_mode();
67a982ee20d20e Miaohe Lin     2021-02-24  1825  	pte_unmap_unlock(mapped_pte, ptl);
42e4089c789072 Andi Kleen     2018-06-13  1826  	return err;
^1da177e4c3f41 Linus Torvalds 2005-04-16  1827  }
^1da177e4c3f41 Linus Torvalds 2005-04-16  1828  

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