This is a note to let you know that I've just added the patch titled RDMA/mlx5: Disable IB_DEVICE_MEM_MGT_EXTENSIONS if IB_WR_REG_MR can't work to the 5.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: rdma-mlx5-disable-ib_device_mem_mgt_extensions-if-ib.patch and it can be found in the queue-5.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 038af9db5d478735ef1eb154b41a99a6d338c8ef Author: Jason Gunthorpe <jgg@xxxxxxxxxx> Date: Mon Sep 14 14:26:52 2020 +0300 RDMA/mlx5: Disable IB_DEVICE_MEM_MGT_EXTENSIONS if IB_WR_REG_MR can't work [ Upstream commit 0ec52f0194638e2d284ad55eba5a7aff753de1b9 ] set_reg_wr() always fails if !umr_modify_entity_size_disabled because mlx5_ib_can_use_umr() always fails. Without set_reg_wr() IB_WR_REG_MR doesn't work and that means the device should not advertise IB_DEVICE_MEM_MGT_EXTENSIONS. Fixes: 841b07f99a47 ("IB/mlx5: Block MR WR if UMR is not possible") Link: https://lore.kernel.org/r/20200914112653.345244-5-leon@xxxxxxxxxx Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index d60d63221b14d..b805cc8124657 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -840,7 +840,9 @@ static int mlx5_ib_query_device(struct ib_device *ibdev, /* We support 'Gappy' memory registration too */ props->device_cap_flags |= IB_DEVICE_SG_GAPS_REG; } - props->device_cap_flags |= IB_DEVICE_MEM_MGT_EXTENSIONS; + /* IB_WR_REG_MR always requires changing the entity size with UMR */ + if (!MLX5_CAP_GEN(dev->mdev, umr_modify_entity_size_disabled)) + props->device_cap_flags |= IB_DEVICE_MEM_MGT_EXTENSIONS; if (MLX5_CAP_GEN(mdev, sho)) { props->device_cap_flags |= IB_DEVICE_INTEGRITY_HANDOVER; /* At this stage no support for signature handover */