From 5d575586c4b320796e9b0bde69065a8a52cd6a7e Mon Sep 17 00:00:00 2001 From: Maxim Mikityanskiy Date: Tue, 18 Jan 2022 13:31:54 +0200 Subject: [PATCH] net/mlx5e: Don't treat small ceil values as unlimited in HTB offload 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 Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/mellanox/mlx5/core/en/qos.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c b/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c index e8a8d78e3e4d5..965838893432d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/qos.c @@ -553,7 +553,8 @@ static int mlx5e_htb_convert_rate(struct mlx5e_priv *priv, u64 rate, 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); -- 2.30.2