在 2018/5/4 20:38, Ruhl, Michael J 写道: >> -----Original Message----- >> From: linux-rdma-owner@xxxxxxxxxxxxxxx [mailto:linux-rdma- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Lijun Ou >> Sent: Thursday, May 3, 2018 10:57 PM >> To: dledford@xxxxxxxxxx; jgg@xxxxxxxxxxxx >> Cc: leon@xxxxxxxxxx; linux-rdma@xxxxxxxxxxxxxxx >> Subject: [PATCH for-rc 11/11] RDMA/hns: Fix the bug with NULL pointer >> >> When the last QP of eight QPs is not exist in >> hns_roce_v1_mr_free_work_fn function, the >> print for qpn of hr_qp may introduce a >> calltrace for NULL pointer. >> >> Signed-off-by: Lijun Ou <oulijun@xxxxxxxxxx> >> --- >> drivers/infiniband/hw/hns/hns_roce_hw_v1.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c >> b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c >> index b3417a9..8013d69 100644 >> --- a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c >> +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c >> @@ -1037,7 +1037,7 @@ static void hns_roce_v1_mr_free_work_fn(struct >> work_struct *work) >> >> do { >> ret = hns_roce_v1_poll_cq(&mr_free_cq->ib_cq, ne, wc); >> - if (ret < 0) { >> + if (ret < 0 && hr_qp) { >> dev_err(dev, >> "(qp:0x%lx) starts, Poll cqe failed(%d) for mr 0x%x >> free! Remain %d cqe\n", >> hr_qp->qpn, ret, hr_mr->key, ne); > > Hi Lijun, > > Previous to your patch, the loop would exit if ret < 0. > > Now, it will continue. Is this what you wanted? > > Mike > Hi，Mike I think it is. I have analysised the algorithm after received your review. The condition of loop exit is poll ne cqe associated non empty hr_qp or timeout.The ret < 0 repsesents that the driver will not lookup the relatived qp caused dirty memory or the hardware exception. As a result, the loop continue is not unncessary. thanks Lijun Ou >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-rdma" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
