RE: [PATCH net-next 01/10] net/smc: add missing dev_put
From: Parav Pandit <hidden>
Date: 2017-10-02 20:36:32
Also in:
linux-rdma, linux-s390
Hi Ursula, Dave, Hans,
quoted hunk ↗ jump to hunk
-----Original Message----- From: linux-rdma-owner@vger.kernel.org [mailto:linux-rdma- owner@vger.kernel.org] On Behalf Of Ursula Braun Sent: Wednesday, September 20, 2017 6:58 AM To: davem@davemloft.net Cc: netdev@vger.kernel.org; linux-rdma@vger.kernel.org; linux- s390@vger.kernel.org; jwi@linux.vnet.ibm.com; schwidefsky@de.ibm.com; heiko.carstens@de.ibm.com; raspl@linux.vnet.ibm.com; ubraun@linux.vnet.ibm.com Subject: [PATCH net-next 01/10] net/smc: add missing dev_put From: Hans Wippel <redacted> In the infiniband part, SMC currently uses get_netdev which calls dev_hold on the returned net device. However, the SMC code never calls dev_put on that net device resulting in a wrong reference count. This patch adds a dev_put after the usage of the net device to fix the issue. Signed-off-by: Hans Wippel <redacted> Signed-off-by: Ursula Braun <redacted> --- net/smc/smc_ib.c | 1 + 1 file changed, 1 insertion(+)diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index547e0e113b17..0b5852299158 100644--- a/net/smc/smc_ib.c +++ b/net/smc/smc_ib.c@@ -380,6 +380,7 @@ static int smc_ib_fill_gid_and_mac(struct smc_ib_device*smcibdev, u8 ibport) ndev = smcibdev->ibdev->get_netdev(smcibdev->ibdev, ibport); if (ndev) { memcpy(&smcibdev->mac, ndev->dev_addr, ETH_ALEN); + dev_put(ndev);
I am sorry for providing late comments. smc_ib_fill_gid_and_mac() is not coded correctly. Few fixes are needed. 1. ULP such as SMC should not open code/deference any function pointer like get_netdev() of the IB device. 2. Replace ib_query_gid(..., NULL) With ib_query_gid(..., gid_attr); Use gid_attr.ndev to get the MAC address. Do dev_put(gid_attr.ndev); Code should look like below, struct ib_gid_attr gid_attr; rc = ib_query_gid(..., &gid_attr); if (rc || !gid_addr.ndev) return -ENODEV; else memcpy(smcibdev->mac, ndev->dev_addr, ETH_ALEN); dev_put(gid_addr.ndev);