tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git master head: f5120f5998803a973b1d432ed2aa7e592527aa46 commit: 48e8c6f1612b3d2dccaea2285231def830cc5b8e [89/100] net: phy: add driver for Motorcomm yt8511 phy config: arm-randconfig-r033-20210522 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project e84a9b9bb3051c35dea993cdad7b3d2575638f85) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit... git remote add net-next https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git git fetch --no-tags net-next master git checkout 48e8c6f1612b3d2dccaea2285231def830cc5b8e # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): if (oldpage < 0) ^~~~~~~~~~~ drivers/net/phy/motorcomm.c:110:43: note: uninitialized use occurs here return phy_restore_page(phydev, oldpage, ret); ^~~ drivers/net/phy/motorcomm.c:58:2: note: remove the 'if' if its condition is always false if (oldpage < 0) ^~~~~~~~~~~~~~~~ drivers/net/phy/motorcomm.c:54:9: note: initialize the variable 'ret' to silence this warning int ret, oldpage; ^ = 0 default: /* leave everything alone in other modes */ ^~~~~~~ drivers/net/phy/motorcomm.c:87:85: note: uninitialized use occurs here ret = __phy_modify(phydev, YT8511_PAGE, (YT8511_DELAY_RX | YT8511_DELAY_GE_TX_EN), ge); ^~ drivers/net/phy/motorcomm.c:53:17: note: initialize the variable 'ge' to silence this warning unsigned int ge, fe; ^ = 0 2 warnings generated. vim +58 drivers/net/phy/motorcomm.c 50 51 static int yt8511_config_init(struct phy_device *phydev) 52 { 53 unsigned int ge, fe; 54 int ret, oldpage; 55 56 /* set clock mode to 125mhz */ 57 oldpage = phy_select_page(phydev, YT8511_EXT_CLK_GATE); 59 goto err_restore_page; 60 61 ret = __phy_modify(phydev, YT8511_PAGE, 0, YT8511_CLK_125M); 62 if (ret < 0) 63 goto err_restore_page; 64 65 /* set rgmii delay mode */ 66 switch (phydev->interface) { 67 case PHY_INTERFACE_MODE_RGMII: 68 ge = YT8511_DELAY_GE_TX_DIS; 69 fe = YT8511_DELAY_FE_TX_DIS; 70 break; 71 case PHY_INTERFACE_MODE_RGMII_RXID: 72 ge = YT8511_DELAY_RX | YT8511_DELAY_GE_TX_DIS; 73 fe = YT8511_DELAY_FE_TX_DIS; 74 break; 75 case PHY_INTERFACE_MODE_RGMII_TXID: 76 ge = YT8511_DELAY_GE_TX_EN; 77 fe = YT8511_DELAY_FE_TX_EN; 78 break; 79 case PHY_INTERFACE_MODE_RGMII_ID: 80 ge = YT8511_DELAY_RX | YT8511_DELAY_GE_TX_EN; 81 fe = YT8511_DELAY_FE_TX_EN; 82 break; 84 break; 85 } 86 87 ret = __phy_modify(phydev, YT8511_PAGE, (YT8511_DELAY_RX | YT8511_DELAY_GE_TX_EN), ge); 88 if (ret < 0) 89 goto err_restore_page; 90 91 /* fast ethernet delay is in a separate page */ 92 ret = __phy_write(phydev, YT8511_PAGE_SELECT, YT8511_EXT_DELAY_DRIVE); 93 if (ret < 0) 94 goto err_restore_page; 95 96 ret = __phy_modify(phydev, YT8511_PAGE, YT8511_DELAY_FE_TX_EN, fe); 97 if (ret < 0) 98 goto err_restore_page; 99 100 /* leave pll enabled in sleep */ 101 ret = __phy_write(phydev, YT8511_PAGE_SELECT, YT8511_EXT_SLEEP_CTRL); 102 if (ret < 0) 103 goto err_restore_page; 104 105 ret = __phy_modify(phydev, YT8511_PAGE, 0, YT8511_PLLON_SLP); 106 if (ret < 0) 107 goto err_restore_page; 108 109 err_restore_page: 110 return phy_restore_page(phydev, oldpage, ret); 111 } 112 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org