[linux-next:master 1888/2932] drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:220:35: warning: variable 'hwvf' is uninitialized when used here

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   7468cbf5c917ec48c66b0dd157b306f36345cab8
commit: 23109f8dd06d0bd04c9360cf7c501c97b0ab1545 [1888/2932] octeontx2-af: Introduce internal packet switching
config: riscv-randconfig-r012-20210722 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9625ca5b602616b2f5584e8a49ba93c52c141e40)
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 riscv cross compiling tool for clang build
        # apt-get install binutils-riscv64-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=23109f8dd06d0bd04c9360cf7c501c97b0ab1545
        git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
        git fetch --no-tags linux-next master
        git checkout 23109f8dd06d0bd04c9360cf7c501c97b0ab1545
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv 

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/net/ethernet/marvell/octeontx2/af/rvu_switch.c:8:
   In file included from drivers/net/ethernet/marvell/octeontx2/af/rvu.h:14:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   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/little_endian.h:36:51: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
                                                     ^
   In file included from drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:8:
   In file included from drivers/net/ethernet/marvell/octeontx2/af/rvu.h:14:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   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/little_endian.h:34:51: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
                                                     ^
   In file included from drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:8:
   In file included from drivers/net/ethernet/marvell/octeontx2/af/rvu.h:14:
   In file included from include/linux/pci.h:38:
   In file included from include/linux/interrupt.h:11:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   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:1024:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
                                                     ~~~~~~~~~~ ^

quoted

drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:220:35: warning: variable 'hwvf' is uninitialized when used here [-Wuninitialized]

                   for (vf = 0; vf < numvfs; vf++, hwvf++) {
                                                   ^~~~
   drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:201:26: note: initialize the variable 'hwvf' to silence this warning
           int pf, vf, numvfs, hwvf;
                                   ^
                                    = 0

quoted

drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:220:21: warning: variable 'numvfs' is uninitialized when used here [-Wuninitialized]

                   for (vf = 0; vf < numvfs; vf++, hwvf++) {
                                     ^~~~~~
   drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c:201:20: note: initialize the variable 'numvfs' to silence this warning
           int pf, vf, numvfs, hwvf;
                             ^
                              = 0
   9 warnings generated.


vim +/hwvf +220 drivers/net/ethernet/marvell/octeontx2/af/rvu_switch.c

   194	
   195	void rvu_switch_disable(struct rvu *rvu)
   196	{
   197		struct npc_delete_flow_req uninstall_req = { 0 };
   198		struct npc_mcam_free_entry_req free_req = { 0 };
   199		struct rvu_switch *rswitch = &rvu->rswitch;
   200		struct rvu_hwinfo *hw = rvu->hw;
   201		int pf, vf, numvfs, hwvf;
   202		struct msg_rsp rsp;
   203		u16 pcifunc;
   204		int err;
   205	
   206		if (!rswitch->used_entries)
   207			return;
   208	
   209		for (pf = 1; pf < hw->total_pfs; pf++) {
   210			if (!is_pf_cgxmapped(rvu, pf))
   211				continue;
   212	
   213			pcifunc = pf << 10;
   214			err = rvu_switch_install_rx_rule(rvu, pcifunc, 0xFFF);
   215			if (err)
   216				dev_err(rvu->dev,
   217					"Reverting RX rule for PF%d failed(%d)\n",
   218					pf, err);
   219	
 > 220			for (vf = 0; vf < numvfs; vf++, hwvf++) {
   221				pcifunc = pf << 10 | ((vf + 1) & 0x3FF);
   222				err = rvu_switch_install_rx_rule(rvu, pcifunc, 0xFFF);
   223				if (err)
   224					dev_err(rvu->dev,
   225						"Reverting RX rule for PF%dVF%d failed(%d)\n",
   226						pf, vf, err);
   227			}
   228		}
   229	
   230		uninstall_req.start = rswitch->start_entry;
   231		uninstall_req.end =  rswitch->start_entry + rswitch->used_entries - 1;
   232		free_req.all = 1;
   233		rvu_mbox_handler_npc_delete_flow(rvu, &uninstall_req, &rsp);
   234		rvu_mbox_handler_npc_mcam_free_entry(rvu, &free_req, &rsp);
   235		rswitch->used_entries = 0;
   236		kfree(rswitch->entry2pcifunc);
   237	}
   238	

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