On 2021/6/18 22:51, kernel test robot wrote:

Hi Dongdong,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on pci/next]
[also build test WARNING on linuxtv-media/master linus/master v5.13-rc6 next-20210618]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210617-041115
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: s390-randconfig-r032-20210618 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 64720f57bea6a6bf033feef4a5751ab9c0c3b401)
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://github.com/0day-ci/linux/commit/caefa7e6d0209bc08eb1934b58dae3aaa0b9dbba
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Dongdong-Liu/PCI-Enable-10-Bit-tag-support-for-PCIe-devices/20210617-041115
        git checkout caefa7e6d0209bc08eb1934b58dae3aaa0b9dbba
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390

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

All warnings (new ones prefixed by >>):

   In file included from drivers/media/pci/cobalt/cobalt-driver.c:18:
   In file included from drivers/media/pci/cobalt/cobalt-driver.h:16:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   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/media/pci/cobalt/cobalt-driver.c:18:
   In file included from drivers/media/pci/cobalt/cobalt-driver.h:16:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   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/media/pci/cobalt/cobalt-driver.c:18:
   In file included from drivers/media/pci/cobalt/cobalt-driver.h:16:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   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);
                   ~~~~~~~~~~ ^

quoted

quoted

drivers/media/pci/cobalt/cobalt-driver.c:199:7: warning: variable 'capa' is uninitialized when used here [-Wuninitialized]

                       capa,
                       ^~~~
   drivers/media/pci/cobalt/cobalt-driver.h:160:71: note: expanded from macro 'cobalt_info'
   #define cobalt_info(fmt, arg...) v4l2_info(&cobalt->v4l2_dev, fmt, ## arg)
                                                                         ^~~
   include/media/v4l2-common.h:67:39: note: expanded from macro 'v4l2_info'
           v4l2_printk(KERN_INFO, dev, fmt , ## arg)
                                                ^~~
   include/media/v4l2-common.h:58:44: note: expanded from macro 'v4l2_printk'
           printk(level "%s: " fmt, (dev)->name , ## arg)
                                                     ^~~
   drivers/media/pci/cobalt/cobalt-driver.c:189:10: note: initialize the variable 'capa' to silence this warning
           u32 capa;
                   ^
                    = 0
   13 warnings generated.


vim +/capa +199 drivers/media/pci/cobalt/cobalt-driver.c

   184	
   185	void cobalt_pcie_status_show(struct cobalt *cobalt)
   186	{
   187		struct pci_dev *pci_dev = cobalt->pci_dev;
   188		struct pci_dev *pci_bus_dev = cobalt->pci_dev->bus->self;
   189		u32 capa;
   190		u16 stat, ctrl;
   191	
   192		if (!pci_is_pcie(pci_dev) || !pci_is_pcie(pci_bus_dev))
   193			return;
   194	
   195		/* Device */
   196		pcie_capability_read_word(pci_dev, PCI_EXP_DEVCTL, &ctrl);
   197		pcie_capability_read_word(pci_dev, PCI_EXP_DEVSTA, &stat);
   198		cobalt_info("PCIe device capability 0x%08x: Max payload %d\n",
 > 199			    capa,

Will fix with pci_dev->pcie_devcap.

Thanks,
Dongdong

   200			    get_payload_size(pci_dev->pcie_devcap & PCI_EXP_DEVCAP_PAYLOAD));
   201		cobalt_info("PCIe device control 0x%04x: Max payload %d. Max read request %d\n",
   202			    ctrl,
   203			    get_payload_size((ctrl & PCI_EXP_DEVCTL_PAYLOAD) >> 5),
   204			    get_payload_size((ctrl & PCI_EXP_DEVCTL_READRQ) >> 12));
   205		cobalt_info("PCIe device status 0x%04x\n", stat);
   206	
   207		/* Link */
   208		pcie_capability_read_dword(pci_dev, PCI_EXP_LNKCAP, &capa);
   209		pcie_capability_read_word(pci_dev, PCI_EXP_LNKCTL, &ctrl);
   210		pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &stat);
   211		cobalt_info("PCIe link capability 0x%08x: %s per lane and %u lanes\n",
   212				capa, get_link_speed(capa),
   213				(capa & PCI_EXP_LNKCAP_MLW) >> 4);
   214		cobalt_info("PCIe link control 0x%04x\n", ctrl);
   215		cobalt_info("PCIe link status 0x%04x: %s per lane and %u lanes\n",
   216			    stat, get_link_speed(stat),
   217			    (stat & PCI_EXP_LNKSTA_NLW) >> 4);
   218	
   219		/* Bus */
   220		pcie_capability_read_dword(pci_bus_dev, PCI_EXP_LNKCAP, &capa);
   221		cobalt_info("PCIe bus link capability 0x%08x: %s per lane and %u lanes\n",
   222				capa, get_link_speed(capa),
   223				(capa & PCI_EXP_LNKCAP_MLW) >> 4);
   224	
   225		/* Slot */
   226		pcie_capability_read_dword(pci_dev, PCI_EXP_SLTCAP, &capa);
   227		pcie_capability_read_word(pci_dev, PCI_EXP_SLTCTL, &ctrl);
   228		pcie_capability_read_word(pci_dev, PCI_EXP_SLTSTA, &stat);
   229		cobalt_info("PCIe slot capability 0x%08x\n", capa);
   230		cobalt_info("PCIe slot control 0x%04x\n", ctrl);
   231		cobalt_info("PCIe slot status 0x%04x\n", stat);
   232	}
   233	

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