Re: [PATCH net-next 1/3] octeontx2-af: Enable CPT HW interrupts

Hi Srujana,

I love your patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Srujana-Challa/octeontx2-af-Miscellaneous-changes-for-CPT/20211011-180247
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 0182d0788cd66292cb1698b48dd21887d93c68ed
config: arm64-randconfig-r034-20211011 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 7ae8f392a1610992c9a925c867fd7238c70d3ce0)
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 arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/4678bed55478a149a9c227e7b2ca51281e9ae83c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Srujana-Challa/octeontx2-af-Miscellaneous-changes-for-CPT/20211011-180247
        git checkout 4678bed55478a149a9c227e7b2ca51281e9ae83c
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=arm64 

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

All warnings (new ones prefixed by >>):

quoted

drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c:49:2: warning: variable 'reg2' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]

           if (!is_rvu_otx2(rvu)) {
           ^~~~~~~~~~~~~~~~~~~~~~
   include/linux/compiler.h:56:28: note: expanded from macro 'if'
   #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/compiler.h:58:30: note: expanded from macro '__trace_if_var'
   #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c:62:48: note: uninitialized use occurs here
           rvu_write64(rvu, blkaddr, CPT_AF_FLTX_INT(2), reg2);
                                                         ^~~~
   drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c:49:2: note: remove the 'if' if its condition is always true
           if (!is_rvu_otx2(rvu)) {
           ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/compiler.h:56:23: note: expanded from macro 'if'
   #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
                         ^
   drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c:45:22: note: initialize the variable 'reg2' to silence this warning
           u64 reg0, reg1, reg2;
                               ^
                                = 0
   1 warning generated.


vim +49 drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c

    39	
    40	static irqreturn_t rvu_cpt_af_flt_intr_handler(int irq, void *ptr)
    41	{
    42		struct rvu_block *block = ptr;
    43		struct rvu *rvu = block->rvu;
    44		int blkaddr = block->addr;
    45		u64 reg0, reg1, reg2;
    46	
    47		reg0 = rvu_read64(rvu, blkaddr, CPT_AF_FLTX_INT(0));
    48		reg1 = rvu_read64(rvu, blkaddr, CPT_AF_FLTX_INT(1));
  > 49		if (!is_rvu_otx2(rvu)) {
    50			reg2 = rvu_read64(rvu, blkaddr, CPT_AF_FLTX_INT(2));
    51			dev_err_ratelimited(rvu->dev,
    52					    "Received CPTAF FLT irq : 0x%llx, 0x%llx, 0x%llx",
    53					     reg0, reg1, reg2);
    54		} else {
    55			dev_err_ratelimited(rvu->dev,
    56					    "Received CPTAF FLT irq : 0x%llx, 0x%llx",
    57					     reg0, reg1);
    58		}
    59	
    60		rvu_write64(rvu, blkaddr, CPT_AF_FLTX_INT(0), reg0);
    61		rvu_write64(rvu, blkaddr, CPT_AF_FLTX_INT(1), reg1);
    62		rvu_write64(rvu, blkaddr, CPT_AF_FLTX_INT(2), reg2);
    63		return IRQ_HANDLED;
    64	}
    65	

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0-DAY CI Kernel Test Service, Intel Corporation
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