[gourryinverse:private_compression 19/60] drivers/dax/kmem.c:216:1: warning: control reaches end of non-void function

[gourryinverse:private_compression 19/60] drivers/dax/kmem.c:216:1: warning: control reaches end of non-void function

[kernel test robot]

tree:   https://github.com/gourryinverse/linux private_compression
head:   9fa5ffee4fd4726e31f05deebb938cccfa0b460f
commit: 5ff2dd414217df1fbed8de6c06536504e2ec2103 [19/60] dax/kmem: add sysfs interface for atomic whole-device hotplug
config: s390-randconfig-002-20260222 (https://download.01.org/0day-ci/archive/20260222/202602221901.2hvPihLP-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260222/202602221901.2hvPihLP-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/202602221901.2hvPihLP-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/dax/kmem.c: In function 'dax_kmem_do_hotremove':
   drivers/dax/kmem.c:215:10: error: 'ENOSUPP' undeclared (first use in this function); did you mean 'ENOTSUPP'?
     return -ENOSUPP;
             ^~~~~~~
             ENOTSUPP
   drivers/dax/kmem.c:215:10: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/dax/kmem.c:216:1: warning: control reaches end of non-void function [-Wreturn-type]
    }
    ^


vim +216 drivers/dax/kmem.c

af7cd15fb8a39f Gregory Price 2026-01-14  166  
af7cd15fb8a39f Gregory Price 2026-01-14  167  #ifdef CONFIG_MEMORY_HOTREMOVE
af7cd15fb8a39f Gregory Price 2026-01-14  168  /**
af7cd15fb8a39f Gregory Price 2026-01-14  169   * dax_kmem_do_hotremove - hot-remove memory for dax kmem device
af7cd15fb8a39f Gregory Price 2026-01-14  170   * @dev_dax: the dev_dax instance
af7cd15fb8a39f Gregory Price 2026-01-14  171   * @data: the dax_kmem_data structure with resource tracking
af7cd15fb8a39f Gregory Price 2026-01-14  172   *
5ff2dd414217df Gregory Price 2026-01-14  173   * Offlines and removes all ranges in the dev_dax region.
af7cd15fb8a39f Gregory Price 2026-01-14  174   *
5ff2dd414217df Gregory Price 2026-01-14  175   * Returns the number of successfully removed ranges, or negative error.
af7cd15fb8a39f Gregory Price 2026-01-14  176   */
af7cd15fb8a39f Gregory Price 2026-01-14  177  static int dax_kmem_do_hotremove(struct dev_dax *dev_dax,
af7cd15fb8a39f Gregory Price 2026-01-14  178  				 struct dax_kmem_data *data)
af7cd15fb8a39f Gregory Price 2026-01-14  179  {
af7cd15fb8a39f Gregory Price 2026-01-14  180  	struct device *dev = &dev_dax->dev;
af7cd15fb8a39f Gregory Price 2026-01-14  181  	int i, success = 0;
af7cd15fb8a39f Gregory Price 2026-01-14  182  
af7cd15fb8a39f Gregory Price 2026-01-14  183  	for (i = 0; i < dev_dax->nr_range; i++) {
af7cd15fb8a39f Gregory Price 2026-01-14  184  		struct range range;
af7cd15fb8a39f Gregory Price 2026-01-14  185  		int rc;
af7cd15fb8a39f Gregory Price 2026-01-14  186  
af7cd15fb8a39f Gregory Price 2026-01-14  187  		rc = dax_kmem_range(dev_dax, i, &range);
af7cd15fb8a39f Gregory Price 2026-01-14  188  		if (rc)
af7cd15fb8a39f Gregory Price 2026-01-14  189  			continue;
af7cd15fb8a39f Gregory Price 2026-01-14  190  
af7cd15fb8a39f Gregory Price 2026-01-14  191  		/* Skip ranges not currently added */
af7cd15fb8a39f Gregory Price 2026-01-14  192  		if (!data->res[i])
af7cd15fb8a39f Gregory Price 2026-01-14  193  			continue;
af7cd15fb8a39f Gregory Price 2026-01-14  194  
5ff2dd414217df Gregory Price 2026-01-14  195  		rc = offline_and_remove_memory(range.start, range_len(&range));
af7cd15fb8a39f Gregory Price 2026-01-14  196  		if (rc == 0) {
af7cd15fb8a39f Gregory Price 2026-01-14  197  			/* Release the resource for the successfully removed range */
af7cd15fb8a39f Gregory Price 2026-01-14  198  			remove_resource(data->res[i]);
af7cd15fb8a39f Gregory Price 2026-01-14  199  			kfree(data->res[i]);
af7cd15fb8a39f Gregory Price 2026-01-14  200  			data->res[i] = NULL;
af7cd15fb8a39f Gregory Price 2026-01-14  201  			success++;
af7cd15fb8a39f Gregory Price 2026-01-14  202  			continue;
af7cd15fb8a39f Gregory Price 2026-01-14  203  		}
af7cd15fb8a39f Gregory Price 2026-01-14  204  		any_hotremove_failed = true;
af7cd15fb8a39f Gregory Price 2026-01-14  205  		dev_err(dev, "mapping%d: %#llx-%#llx hotremove failed\n",
af7cd15fb8a39f Gregory Price 2026-01-14  206  			i, range.start, range.end);
af7cd15fb8a39f Gregory Price 2026-01-14  207  	}
af7cd15fb8a39f Gregory Price 2026-01-14  208  
af7cd15fb8a39f Gregory Price 2026-01-14  209  	return success;
af7cd15fb8a39f Gregory Price 2026-01-14  210  }
af7cd15fb8a39f Gregory Price 2026-01-14  211  #else
af7cd15fb8a39f Gregory Price 2026-01-14  212  static int dax_kmem_do_hotremove(struct dev_dax *dev_dax,
af7cd15fb8a39f Gregory Price 2026-01-14  213  				 struct dax_kmem_data *data)
af7cd15fb8a39f Gregory Price 2026-01-14  214  {
af7cd15fb8a39f Gregory Price 2026-01-14  215  	return -ENOSUPP;
af7cd15fb8a39f Gregory Price 2026-01-14 @216  }
af7cd15fb8a39f Gregory Price 2026-01-14  217  #endif /* CONFIG_MEMORY_HOTREMOVE */
af7cd15fb8a39f Gregory Price 2026-01-14  218  

:::::: The code at line 216 was first introduced by commit
:::::: af7cd15fb8a39fb0d8799c2d54dae5864d67632b dax/kmem: extract hotplug/hotremove helper functions

:::::: TO: Gregory Price <gourry@gourry.net>
:::::: CC: Gregory Price <gourry@gourry.net>

-- 
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https://github.com/intel/lkp-tests/wiki