Hi Ursula, Dave, Hans,
> -----Original Message-----
> From: linux-rdma-ow...@vger.kernel.org [mailto:linux-rdma-
> ow...@vger.kernel.org] On Behalf Of Ursula Braun
> Sent: Wednesday, September 20, 2017 6:58 AM
> To: da...@davemloft.net
> Cc: netdev@vger.kernel.org; linux-r...@vger.kernel.org; linux-
> s...@vger.kernel.org; j...@linux.vnet.ibm.com; schwidef...@de.ibm.com;
> heiko.carst...@de.ibm.com; ra...@linux.vnet.ibm.com;
> ubr...@linux.vnet.ibm.com
> Subject: [PATCH net-next 01/10] net/smc: add missing dev_put
>
> From: Hans Wippel <hwip...@linux.vnet.ibm.com>
>
> 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 <hwip...@linux.vnet.ibm.com>
> Signed-off-by: Ursula Braun <ubr...@linux.vnet.ibm.com>
> ---
> 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 index
> 547e0e113b17..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);
