From: Leon Romanovsky Date: Mon, 3 Sep 2018 06:11:14 +0000 (+0300) Subject: RDMA/mlx4: Ensure that maximal send/receive SGE less than supported by HW X-Git-Tag: v4.19-rc4~37^2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8f28b178f71cc56eccf2a6e2c0ace17c82f900d7;p=thirdparty%2Flinux.git RDMA/mlx4: Ensure that maximal send/receive SGE less than supported by HW In calculating the global maximum number of the Scatter/Gather elements supported, the following four maximum parameters must be taken into consideration: max_sg_rq, max_sg_sq, max_desc_sz_rq and max_desc_sz_sq. However instead of bringing this complexity to query_device, which still won't be sufficient anyway (the calculations are dependent on QP type), the safer approach will be to restore old code, which will give us 32 SGEs. Fixes: 33023fb85a42 ("IB/core: add max_send_sge and max_recv_sge attributes") Reported-by: Chuck Lever Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c index ca0f1ee26091b..0bbeaaae47e07 100644 --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -517,9 +517,11 @@ static int mlx4_ib_query_device(struct ib_device *ibdev, props->page_size_cap = dev->dev->caps.page_size_cap; props->max_qp = dev->dev->quotas.qp; props->max_qp_wr = dev->dev->caps.max_wqes - MLX4_IB_SQ_MAX_SPARE; - props->max_send_sge = dev->dev->caps.max_sq_sg; - props->max_recv_sge = dev->dev->caps.max_rq_sg; - props->max_sge_rd = MLX4_MAX_SGE_RD; + props->max_send_sge = + min(dev->dev->caps.max_sq_sg, dev->dev->caps.max_rq_sg); + props->max_recv_sge = + min(dev->dev->caps.max_sq_sg, dev->dev->caps.max_rq_sg); + props->max_sge_rd = MLX4_MAX_SGE_RD; props->max_cq = dev->dev->quotas.cq; props->max_cqe = dev->dev->caps.max_cqes; props->max_mr = dev->dev->quotas.mpt;