RDMA/mlx4: Read pkey table length instead of hardcoded value

commit ec78b3bd66bc9a015505df0ef0eb153d9e64b03b upstream.

If the pkey_table is not available (which is the case when RoCE is not
supported), the cited commit caused a regression where mlx4_devices
without RoCE are not created.

Fix this by returning a pkey table length of zero in procedure
eth_link_query_port() if the pkey-table length reported by the device is
zero.

Link: https://lore.kernel.org/r/20200824110229.1094376-1-leon@kernel.org
Cc: <stable@vger.kernel.org>
Fixes: 1901b91f9982 ("IB/core: Fix potential NULL pointer dereference in pkey cache")
Fixes: fa417f7b520e ("IB/mlx4: Add support for IBoE")
Signed-off-by: Mark Bloch <markb@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 816d28854a8e11a8d21a081b2adb60715e72e502..5bcf481a9c3c253793185698ee35c2a497b292c2 100644 (file)
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -784,7 +784,8 @@ static int eth_link_query_port(struct ib_device *ibdev, u8 port,
        props->ip_gids = true;
        props->gid_tbl_len      = mdev->dev->caps.gid_table_len[port];
        props->max_msg_sz       = mdev->dev->caps.max_msg_sz;
-       props->pkey_tbl_len     = 1;
+       if (mdev->dev->caps.pkey_table_len[port])
+               props->pkey_tbl_len = 1;
        props->max_mtu          = IB_MTU_4096;
        props->max_vl_num       = 2;
        props->state            = IB_PORT_DOWN;