From: Maxim Mikityanskiy <maximmi@xxxxxxxxxx> commit 736dfe4e68b868829a1e89dfef4a44c1580d4478 upstream. The hardware spec defines max_average_bw == 0 as "unlimited bandwidth". max_average_bw is calculated as `ceil / BYTES_IN_MBIT`, which can become 0 when ceil is small, leading to an undesired effect of having no bandwidth limit. This commit fixes it by rounding up small values of ceil to 1 Mbit/s. Fixes: 214baf22870c ("net/mlx5e: Support HTB offload") Signed-off-by: Maxim Mikityanskiy <maximmi@xxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlx5/core/en/qos.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c @@ -569,7 +569,8 @@ static int mlx5e_htb_convert_rate(struct static void mlx5e_htb_convert_ceil(struct mlx5e_priv *priv, u64 ceil, u32 *max_average_bw) { - *max_average_bw = div_u64(ceil, BYTES_IN_MBIT); + /* Hardware treats 0 as "unlimited", set at least 1. */ + *max_average_bw = max_t(u32, div_u64(ceil, BYTES_IN_MBIT), 1); qos_dbg(priv->mdev, "Convert: ceil %llu -> max_average_bw %u\n", ceil, *max_average_bw);