From 6ef07a9f369742a7b18c77484411cff0bd790291 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Sun, 8 Jun 2014 10:00:59 +0300 Subject: [PATCH] mlx5_core: Fix possible race between mr tree insert/delete In mlx5_core_destroy_mkey(), we must first remove the mr from the radix tree and then destroy it. Otherwise we might hit a race if the key was reallocated and we attempted to insert it to the radix tree. Also handle radix tree insert/delete failures. Signed-off-by: Sagi Grimberg Reviewed-by: Eli Cohen Signed-off-by: Roland Dreier --- drivers/net/ethernet/mellanox/mlx5/core/mr.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/mr.c b/drivers/net/ethernet/mellanox/mlx5/core/mr.c index ba0401d4af50..184c3615f479 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/mr.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/mr.c @@ -94,6 +94,11 @@ int mlx5_core_create_mkey(struct mlx5_core_dev *dev, struct mlx5_core_mr *mr, write_lock_irq(&table->lock); err = radix_tree_insert(&table->tree, mlx5_base_mkey(mr->key), mr); write_unlock_irq(&table->lock); + if (err) { + mlx5_core_warn(dev, "failed radix tree insert of mr 0x%x, %d\n", + mlx5_base_mkey(mr->key), err); + mlx5_core_destroy_mkey(dev, mr); + } return err; } @@ -104,12 +109,22 @@ int mlx5_core_destroy_mkey(struct mlx5_core_dev *dev, struct mlx5_core_mr *mr) struct mlx5_mr_table *table = &dev->priv.mr_table; struct mlx5_destroy_mkey_mbox_in in; struct mlx5_destroy_mkey_mbox_out out; + struct mlx5_core_mr *deleted_mr; unsigned long flags; int err; memset(&in, 0, sizeof(in)); memset(&out, 0, sizeof(out)); + write_lock_irqsave(&table->lock, flags); + deleted_mr = radix_tree_delete(&table->tree, mlx5_base_mkey(mr->key)); + write_unlock_irqrestore(&table->lock, flags); + if (!deleted_mr) { + mlx5_core_warn(dev, "failed radix tree delete of mr 0x%x\n", + mlx5_base_mkey(mr->key)); + return -ENOENT; + } + in.hdr.opcode = cpu_to_be16(MLX5_CMD_OP_DESTROY_MKEY); in.mkey = cpu_to_be32(mlx5_mkey_to_idx(mr->key)); err = mlx5_cmd_exec(dev, &in, sizeof(in), &out, sizeof(out)); @@ -119,10 +134,6 @@ int mlx5_core_destroy_mkey(struct mlx5_core_dev *dev, struct mlx5_core_mr *mr) if (out.hdr.status) return mlx5_cmd_status_to_err(&out.hdr); - write_lock_irqsave(&table->lock, flags); - radix_tree_delete(&table->tree, mlx5_base_mkey(mr->key)); - write_unlock_irqrestore(&table->lock, flags); - return err; } EXPORT_SYMBOL(mlx5_core_destroy_mkey); -- 2.20.1