[intel-lts:pr/59 1/1] drivers/net/ethernet/hisilicon/hns/hns_ethtool.c:309:7: warning: this statement may fall through

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

tree:   https://github.com/intel/linux-intel-lts.git pr/59
head:   19ae9bc73680fd6c1c95edb5b7e2aaa790e7f011
commit: 67cd9a997f1bfb5dedf407ad540232912bd04b10 [1/1] net: hns: Use phy_driver to setup Phy loopback
config: xtensa-randconfig-002-20250218 (https://download.01.org/0day-ci/archive/20250221/202502211515.UVZCsumx-lkp@intel.com/config)
compiler: xtensa-linux-gcc (GCC) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250221/202502211515.UVZCsumx-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/202502211515.UVZCsumx-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/linkage.h:4:0,
                    from include/linux/kernel.h:6,
                    from include/linux/skbuff.h:17,
                    from include/linux/if_ether.h:23,
                    from include/linux/etherdevice.h:25,
                    from drivers/net/ethernet/hisilicon/hns/hns_ethtool.c:10:
   include/linux/dma-mapping.h: In function 'dma_map_resource':
   arch/xtensa/include/asm/page.h:185:9: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
     ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr)
            ^
   include/linux/compiler.h:179:42: note: in definition of macro 'unlikely'
    # define unlikely(x) __builtin_expect(!!(x), 0)
                                             ^
   include/linux/dma-mapping.h:308:2: note: in expansion of macro 'BUG_ON'
     BUG_ON(pfn_valid(PHYS_PFN(phys_addr)));
     ^~~~~~
   include/linux/dma-mapping.h:308:9: note: in expansion of macro 'pfn_valid'
     BUG_ON(pfn_valid(PHYS_PFN(phys_addr)));
            ^~~~~~~~~
   drivers/net/ethernet/hisilicon/hns/hns_ethtool.c: In function '__lb_setup':
>> drivers/net/ethernet/hisilicon/hns/hns_ethtool.c:309:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
      ret = hns_nic_config_phy_loopback(phy_dev, 0x0);
      ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/net/ethernet/hisilicon/hns/hns_ethtool.c:310:2: note: here
     case MAC_LOOP_NONE:
     ^~~~
   In file included from include/linux/string.h:18:0,
                    from include/linux/bitmap.h:8,
                    from include/linux/cpumask.h:11,
                    from include/linux/mm_types_task.h:13,
                    from include/linux/mm_types.h:4,
                    from include/linux/kmemcheck.h:4,
                    from include/linux/skbuff.h:18,
                    from include/linux/if_ether.h:23,
                    from include/linux/etherdevice.h:25,
                    from drivers/net/ethernet/hisilicon/hns/hns_ethtool.c:10:
   drivers/net/ethernet/hisilicon/hns/hns_ethtool.c: In function 'hns_nic_get_drvinfo':
   arch/xtensa/include/asm/string.h:56:42: warning: array subscript is above array bounds [-Warray-bounds]
      : "0" (__dest), "1" (__src), "r" (__src+__n)
                                        ~~~~~^~~~
   arch/xtensa/include/asm/string.h:56:42: warning: array subscript is above array bounds [-Warray-bounds]
      : "0" (__dest), "1" (__src), "r" (__src+__n)
                                        ~~~~~^~~~
   arch/xtensa/include/asm/string.h:56:42: warning: array subscript is above array bounds [-Warray-bounds]
      : "0" (__dest), "1" (__src), "r" (__src+__n)
                                        ~~~~~^~~~


vim +309 drivers/net/ethernet/hisilicon/hns/hns_ethtool.c

   284	
   285	static int __lb_setup(struct net_device *ndev,
   286			      enum hnae_loop loop)
   287	{
   288		int ret = 0;
   289		struct hns_nic_priv *priv = netdev_priv(ndev);
   290		struct phy_device *phy_dev = ndev->phydev;
   291		struct hnae_handle *h = priv->ae_handle;
   292	
   293		switch (loop) {
   294		case MAC_INTERNALLOOP_PHY:
   295			ret = hns_nic_config_phy_loopback(phy_dev, 0x1);
   296			if (!ret)
   297				ret = h->dev->ops->set_loopback(h, loop, 0x1);
   298			break;
   299		case MAC_INTERNALLOOP_MAC:
   300			if ((h->dev->ops->set_loopback) &&
   301			    (priv->ae_handle->phy_if != PHY_INTERFACE_MODE_XGMII))
   302				ret = h->dev->ops->set_loopback(h, loop, 0x1);
   303			break;
   304		case MAC_INTERNALLOOP_SERDES:
   305			if (h->dev->ops->set_loopback)
   306				ret = h->dev->ops->set_loopback(h, loop, 0x1);
   307			break;
   308		case MAC_LOOP_PHY_NONE:
 > 309			ret = hns_nic_config_phy_loopback(phy_dev, 0x0);
   310		case MAC_LOOP_NONE:
   311			if (!ret && h->dev->ops->set_loopback) {
   312				if (priv->ae_handle->phy_if != PHY_INTERFACE_MODE_XGMII)
   313					ret = h->dev->ops->set_loopback(h,
   314						MAC_INTERNALLOOP_MAC, 0x0);
   315	
   316				if (!ret)
   317					ret = h->dev->ops->set_loopback(h,
   318						MAC_INTERNALLOOP_SERDES, 0x0);
   319			}
   320			break;
   321		default:
   322			ret = -EINVAL;
   323			break;
   324		}
   325	
   326		if (!ret) {
   327			if (loop == MAC_LOOP_NONE)
   328				h->dev->ops->set_promisc_mode(
   329					h, ndev->flags & IFF_PROMISC);
   330			else
   331				h->dev->ops->set_promisc_mode(h, 1);
   332		}
   333		return ret;
   334	}
   335	

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