net/mlx5: Fix error handling in irq_pool_request_irq

[ Upstream commit a4557b0b57c40871ff00da4f623cf79211e052f3 ]

In case mlx5_irq_alloc fails, the previously allocated index remains
in the XArray, which could lead to inconsistencies.

Fix it by adding error handling that erases the allocated index
from the XArray if mlx5_irq_alloc returns an error.

Fixes: c36326d38d93 ("net/mlx5: Round-Robin EQs over IRQs")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Maher Sanalla <msanalla@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Link: https://patch.msgid.link/20240730061638.1831002-3-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/irq_affinity.c b/drivers/net/ethernet/mellanox/mlx5/core/irq_affinity.c
index 612e666ec2635614f2e24443f319efd822b369b5..e2230c8f18152fbb8f9495dd6f3b1ba5c598b0c8 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/irq_affinity.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/irq_affinity.c
@@ -48,6 +48,7 @@ static struct mlx5_irq *
 irq_pool_request_irq(struct mlx5_irq_pool *pool, struct irq_affinity_desc *af_desc)
 {
        struct irq_affinity_desc auto_desc = {};
+       struct mlx5_irq *irq;
        u32 irq_index;
        int err;
 
@@ -64,9 +65,12 @@ irq_pool_request_irq(struct mlx5_irq_pool *pool, struct irq_affinity_desc *af_de
                else
                        cpu_get(pool, cpumask_first(&af_desc->mask));
        }
-       return mlx5_irq_alloc(pool, irq_index,
-                             cpumask_empty(&auto_desc.mask) ? af_desc : &auto_desc,
-                             NULL);
+       irq = mlx5_irq_alloc(pool, irq_index,
+                            cpumask_empty(&auto_desc.mask) ? af_desc : &auto_desc,
+                            NULL);
+       if (IS_ERR(irq))
+               xa_erase(&pool->irqs, irq_index);
+       return irq;
 }
 
 /* Looking for the IRQ with the smallest refcount that fits req_mask.