net/mlx5: LAG, allocate port-indexed scratch buffers dynamically

mlx5_lag_print_mapping(), mlx5_infer_tx_affinity_mapping() and
lag_active_port_bits() each used a MLX5_MAX_PORTS-sized stack buffer to
hold per-port working state. Allocate these buffers with
kcalloc(ldev->ports, ...) instead so they track the actual port count
and no longer depend on MLX5_MAX_PORTS.

lag_active_port_bits() can now fail on allocation, so it returns int and
propagates -ENOMEM; a non-negative return is the active-port bitmask as
before. Its two callers, mlx5_cmd_create_lag() and _mlx5_modify_lag(),
check for a negative return and bail out, then narrow the value back
into the u8 they hand to the device.

This removes these buffers' dependency on MLX5_MAX_PORTS.

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Akiva Goldberger <agoldberger@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20260923103830.1183-5-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Shay Drory 2026-09-23 13:38:21 +03:00 • committed by Jakub Kicinski
commit 4138820bdd