Hi Vishal, I love your patch! Perhaps something to improve: [auto build test WARNING on net/master] url: https://github.com/0day-ci/linux/commits/Vishal-Kulkarni/cxgb4-fix-out-of-bounds-MSI-X-info-array-access/20191001-134119 config: sparc64-allmodconfig (attached as .config) compiler: sparc64-linux-gcc (GCC) 7.4.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree GCC_VERSION=7.4.0 make.cross ARCH=sparc64 If you fix the issue, kindly add following tag Reported-by: kbuild test robot Note: it may well be a FALSE warning. FWIW you are at least aware of it now. http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings All warnings (new ones prefixed by >>): drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c: In function 'cxgb4_register_uld': >> drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c:179:26: warning: 'bmap_idx' may be used uninitialized in this function [-Wmaybe-uninitialized] rxq_info->msix_tbl[i] = bmap_idx; ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~ drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c:141:14: note: 'bmap_idx' was declared here int i, err, bmap_idx, msi_idx, que_idx = 0; ^~~~~~~~ vim +/bmap_idx +179 drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 136 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 137 static int alloc_uld_rxqs(struct adapter *adap, 166e6045cacccb Ganesh Goudar 2016-10-26 138 struct sge_uld_rxq_info *rxq_info, bool lro) 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 139 { 166e6045cacccb Ganesh Goudar 2016-10-26 140 unsigned int nq = rxq_info->nrxq + rxq_info->nciq; 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 141 int i, err, bmap_idx, msi_idx, que_idx = 0; 166e6045cacccb Ganesh Goudar 2016-10-26 142 struct sge_ofld_rxq *q = rxq_info->uldrxq; 166e6045cacccb Ganesh Goudar 2016-10-26 143 unsigned short *ids = rxq_info->rspq_id; 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 144 struct sge *s = &adap->sge; 166e6045cacccb Ganesh Goudar 2016-10-26 145 unsigned int per_chan; 166e6045cacccb Ganesh Goudar 2016-10-26 146 166e6045cacccb Ganesh Goudar 2016-10-26 147 per_chan = rxq_info->nrxq / adap->params.nports; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 148 80f61f19e542ae Arjun Vynipadath 2019-03-04 149 if (adap->flags & CXGB4_USING_MSIX) 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 150 msi_idx = 1; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 151 else 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 152 msi_idx = -((int)s->intrq.abs_id + 1); 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 153 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 154 for (i = 0; i < nq; i++, q++) { 166e6045cacccb Ganesh Goudar 2016-10-26 155 if (i == rxq_info->nrxq) { 166e6045cacccb Ganesh Goudar 2016-10-26 156 /* start allocation of concentrator queues */ 166e6045cacccb Ganesh Goudar 2016-10-26 157 per_chan = rxq_info->nciq / adap->params.nports; 166e6045cacccb Ganesh Goudar 2016-10-26 158 que_idx = 0; 166e6045cacccb Ganesh Goudar 2016-10-26 159 } 166e6045cacccb Ganesh Goudar 2016-10-26 160 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 161 if (msi_idx >= 0) { 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 162 bmap_idx = get_msix_idx_from_bmap(adap); 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 163 if (bmap_idx < 0) { 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 164 err = -ENOSPC; 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 165 goto freeout; 18492f3ba5cfcc Vishal Kulkarni 2019-10-01 166 } 0fbc81b3ad513f Hariprasad Shenai 2016-09-17 167 msi_idx = adap->msix_info_ulds[bmap_idx].idx; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 168 } 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 169 err = t4_sge_alloc_rxq(adap, &q->rspq, false, 166e6045cacccb Ganesh Goudar 2016-10-26 170 adap->port[que_idx++ / per_chan], 0fbc81b3ad513f Hariprasad Shenai 2016-09-17 171 msi_idx, 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 172 q->fl.size ? &q->fl : NULL, 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 173 uldrx_handler, 0fbc81b3ad513f Hariprasad Shenai 2016-09-17 174 lro ? uldrx_flush_handler : NULL, 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 175 0); 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 176 if (err) 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 177 goto freeout; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 178 if (msi_idx >= 0) 166e6045cacccb Ganesh Goudar 2016-10-26 @179 rxq_info->msix_tbl[i] = bmap_idx; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 180 memset(&q->stats, 0, sizeof(q->stats)); 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 181 if (ids) 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 182 ids[i] = q->rspq.abs_id; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 183 } 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 184 return 0; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 185 freeout: 166e6045cacccb Ganesh Goudar 2016-10-26 186 q = rxq_info->uldrxq; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 187 for ( ; i; i--, q++) { 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 188 if (q->rspq.desc) 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 189 free_rspq_fl(adap, &q->rspq, 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 190 q->fl.size ? &q->fl : NULL); 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 191 } 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 192 return err; 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 193 } 94cdb8bb993a23 Hariprasad Shenai 2016-08-17 194 :::::: The code at line 179 was first introduced by commit :::::: 166e6045cacccb3046883a1a4c977f173fec5ccd cxgb4: Fix error handling in alloc_uld_rxqs(). :::::: TO: Ganesh Goudar :::::: CC: David S. 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