drivers/net/ethernet/mediatek/mtk_star_emac.c:1559:34: warning: unused variable 'mtk_star_of_match'

From: kernel test robot
Date: Wed Jan 26 2022 - 04:01:50 EST


Hi Lorenzo,

First bad commit (maybe != root cause):

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 0280e3c58f92b2fe0e8fbbdf8d386449168de4a8
commit: a3c62a042237d1adeb0290dcb768e17edd6dcd25 net: mtk_eth: add COMPILE_TEST support
date: 6 weeks ago
config: s390-buildonly-randconfig-r005-20220126 (https://download.01.org/0day-ci/archive/20220126/202201261608.BLH8XrDI-lkp@xxxxxxxxx/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 2a1b7aa016c0f4b5598806205bdfbab1ea2d92c4)
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 s390 cross compiling tool for clang build
# apt-get install binutils-s390x-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a3c62a042237d1adeb0290dcb768e17edd6dcd25
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout a3c62a042237d1adeb0290dcb768e17edd6dcd25
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/net/ethernet/mediatek/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:36:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from drivers/net/ethernet/mediatek/mtk_star_emac.c:12:
In file included from include/linux/dma-mapping.h:10:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:75:
include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> drivers/net/ethernet/mediatek/mtk_star_emac.c:1559:34: warning: unused variable 'mtk_star_of_match' [-Wunused-const-variable]
static const struct of_device_id mtk_star_of_match[] = {
^
13 warnings generated.


vim +/mtk_star_of_match +1559 drivers/net/ethernet/mediatek/mtk_star_emac.c

8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1558
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 @1559 static const struct of_device_id mtk_star_of_match[] = {
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1560 { .compatible = "mediatek,mt8516-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1561 { .compatible = "mediatek,mt8518-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1562 { .compatible = "mediatek,mt8175-eth", },
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1563 { }
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1564 };
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1565 MODULE_DEVICE_TABLE(of, mtk_star_of_match);
8c7bd5a454ffc2 Bartosz Golaszewski 2020-05-22 1566

:::::: The code at line 1559 was first introduced by commit
:::::: 8c7bd5a454ffc2b0518d1499c4af95f00291d2af net: ethernet: mtk-star-emac: new driver

:::::: TO: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
:::::: CC: David S. Miller <davem@xxxxxxxxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
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