Re: [PATCH] IB/ipoib: Skip napi_schedule if ib_poll_cq fails

Hi,

[auto build test WARNING on rdma/master]
[also build test WARNING on v4.7-rc7 next-20160712]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Yuval-Shaia/IB-ipoib-Skip-napi_schedule-if-ib_poll_cq-fails/20160713-173838
base:   https://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma.git master
config: ia64-defconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 4.9.0
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=ia64 

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/infiniband/ulp/ipoib/ipoib_ib.c: In function 'ipoib_poll':

quoted

drivers/infiniband/ulp/ipoib/ipoib_ib.c:478:5: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]

     if (unlikely(n < 0) && (n != -EAGAIN)) {
        ^

vim +/n +478 drivers/infiniband/ulp/ipoib/ipoib_ib.c

   462				struct ib_wc *wc = priv->ibwc + i;
   463	
   464				if (wc->wr_id & IPOIB_OP_RECV) {
   465					++done;
   466					if (wc->wr_id & IPOIB_OP_CM)
   467						ipoib_cm_handle_rx_wc(dev, wc);
   468					else
   469						ipoib_ib_handle_rx_wc(dev, wc);
   470				} else
   471					ipoib_cm_handle_tx_wc(priv->dev, wc);
   472			}
   473	
   474			if (n != t)
   475				break;
   476		}
   477	
 > 478		if (unlikely(n < 0) && (n != -EAGAIN)) {
   479			if (priv->recv_conseq_cq_errs++ >= IPOIB_MAX_CONSEQ_CQ_ERR) {
   480				ipoib_crit(priv,
   481					   "Too many poll_cq errors, last error: %d\n",
   482					   n);
   483				return done;
   484			}
   485		} else
   486			priv->recv_conseq_cq_errs = 0;

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation