[akpm-mm:mm-new 114/114] mm/vmalloc.c:191 vmap_pmd_range() error: uninitialized symbol 'err'.

[Dan Carpenter <dan.carpenter@linaro.org>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-new
head:   dbf0247637dd0601a462793035bdd0b416b30e36
commit: dbf0247637dd0601a462793035bdd0b416b30e36 [114/114] mm: vmalloc: WARN_ON if mapping size is not PAGE_SIZE aligned
config: sparc-randconfig-r071-20251010 (https://download.01.org/0day-ci/archive/20251011/202510110050.VG9YKMRK-lkp@intel.com/config)
compiler: sparc-linux-gcc (GCC) 8.5.0

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>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202510110050.VG9YKMRK-lkp@intel.com/

smatch warnings:
mm/vmalloc.c:191 vmap_pmd_range() error: uninitialized symbol 'err'.
mm/vmalloc.c:243 vmap_pud_range() error: uninitialized symbol 'err'.
mm/vmalloc.c:295 vmap_p4d_range() error: uninitialized symbol 'err'.

vim +/err +191 mm/vmalloc.c

5e9e3d777b99aa Nicholas Piggin 2021-04-29  167  static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
5e9e3d777b99aa Nicholas Piggin 2021-04-29  168  			phys_addr_t phys_addr, pgprot_t prot,
5e9e3d777b99aa Nicholas Piggin 2021-04-29  169  			unsigned int max_page_shift, pgtbl_mod_mask *mask)
5e9e3d777b99aa Nicholas Piggin 2021-04-29  170  {
5e9e3d777b99aa Nicholas Piggin 2021-04-29  171  	pmd_t *pmd;
5e9e3d777b99aa Nicholas Piggin 2021-04-29  172  	unsigned long next;
dbf0247637dd06 Yadong Qi       2025-10-10  173  	int err;
5e9e3d777b99aa Nicholas Piggin 2021-04-29  174  
5e9e3d777b99aa Nicholas Piggin 2021-04-29  175  	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
5e9e3d777b99aa Nicholas Piggin 2021-04-29  176  	if (!pmd)
5e9e3d777b99aa Nicholas Piggin 2021-04-29  177  		return -ENOMEM;
5e9e3d777b99aa Nicholas Piggin 2021-04-29  178  	do {
5e9e3d777b99aa Nicholas Piggin 2021-04-29  179  		next = pmd_addr_end(addr, end);
5e9e3d777b99aa Nicholas Piggin 2021-04-29  180  
5e9e3d777b99aa Nicholas Piggin 2021-04-29  181  		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
5e9e3d777b99aa Nicholas Piggin 2021-04-29  182  					max_page_shift)) {
5e9e3d777b99aa Nicholas Piggin 2021-04-29  183  			*mask |= PGTBL_PMD_MODIFIED;
5e9e3d777b99aa Nicholas Piggin 2021-04-29  184  			continue;

Is it possible to hit the continue on every iteration through the loop?

5e9e3d777b99aa Nicholas Piggin 2021-04-29  185  		}
5e9e3d777b99aa Nicholas Piggin 2021-04-29  186  
dbf0247637dd06 Yadong Qi       2025-10-10  187  		err = vmap_pte_range(pmd, addr, next, phys_addr, prot, max_page_shift, mask);
dbf0247637dd06 Yadong Qi       2025-10-10  188  		if (err)
dbf0247637dd06 Yadong Qi       2025-10-10  189  			break;

I always feel like these are better as a "return ret;" anyway.  Then it's
just one line to read instead of needing to "break; ... return err;".
Twice as fast to read one line vs two lines.

5e9e3d777b99aa Nicholas Piggin 2021-04-29  190  	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
dbf0247637dd06 Yadong Qi       2025-10-10 @191  	return err;
5e9e3d777b99aa Nicholas Piggin 2021-04-29  192  }

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