Re: [PATCH 18/26] mm: asi: Map vmalloc/vmap data as nonsesnitive

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

Hi Brendan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on a38297e3fb012ddfa7ce0321a7e5a8daeb1872b6]

url:    https://github.com/intel-lab-lkp/linux/commits/Brendan-Jackman/mm-asi-Make-some-utility-functions-noinstr-compatible/20240713-012107
base:   a38297e3fb012ddfa7ce0321a7e5a8daeb1872b6
patch link:    https://lore.kernel.org/r/20240712-asi-rfc-24-v1-18-144b319a40d8%40google.com
patch subject: [PATCH 18/26] mm: asi: Map vmalloc/vmap data as nonsesnitive
config: openrisc-allnoconfig (https://download.01.org/0day-ci/archive/20240713/202407132325.YotidwGR-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240713/202407132325.YotidwGR-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/202407132325.YotidwGR-lkp@intel.com/

All warnings (new ones prefixed by >>):

   mm/vmalloc.c: In function 'remove_vm_area':
>> mm/vmalloc.c:3192:23: warning: variable 'vm_addr' set but not used [-Wunused-but-set-variable]
    3192 |         unsigned long vm_addr;
         |                       ^~~~~~~


vim +/vm_addr +3192 mm/vmalloc.c

  3177	
  3178	/**
  3179	 * remove_vm_area - find and remove a continuous kernel virtual area
  3180	 * @addr:	    base address
  3181	 *
  3182	 * Search for the kernel VM area starting at @addr, and remove it.
  3183	 * This function returns the found VM area, but using it is NOT safe
  3184	 * on SMP machines, except for its size or flags.
  3185	 *
  3186	 * Return: the area descriptor on success or %NULL on failure.
  3187	 */
  3188	struct vm_struct *remove_vm_area(const void *addr)
  3189	{
  3190		struct vmap_area *va;
  3191		struct vm_struct *vm;
> 3192		unsigned long vm_addr;
  3193	
  3194		might_sleep();
  3195	
  3196		if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
  3197				addr))
  3198			return NULL;
  3199	
  3200		va = find_unlink_vmap_area((unsigned long)addr);
  3201		if (!va || !va->vm)
  3202			return NULL;
  3203		vm = va->vm;
  3204		vm_addr = (unsigned long) READ_ONCE(vm->addr);
  3205	
  3206		debug_check_no_locks_freed(vm->addr, get_vm_area_size(vm));
  3207		debug_check_no_obj_freed(vm->addr, get_vm_area_size(vm));
  3208		kasan_free_module_shadow(vm);
  3209		kasan_poison_vmalloc(vm->addr, get_vm_area_size(vm));
  3210	
  3211		free_unmap_vmap_area(va);
  3212		return vm;
  3213	}
  3214	

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