[PATCH net RESEND] net/mlx5e: kTLS, Fix missing error unwind when enabling RX offload

[PATCH net RESEND] net/mlx5e: kTLS, Fix missing error unwind when enabling RX offload

[Tariq Toukan]

From: Xuanqiang Luo <luoxuanqiang@kylinos.cn>

Since commit abed42f9cd80 ("net/mlx5e: Conditionally create async
ICOSQ"), the async ICOSQ is only created when an XDP program is attached
or priv->ktls_rx_was_enabled is set. When TLS RX offload is enabled for
the first time, mlx5e_ktls_set_feature_rx() sets the flag and reopens
the channels so that they get the queue, but it ignores the return value
of mlx5e_safe_reopen_channels().

If the reopen fails, mlx5e_safe_switch_params() keeps the old channels,
which have no async ICOSQ, while NETIF_F_HW_TLS_RX is still reported as
enabled. The next offloaded RX connection then dereferences the NULL
c->async_icosq in post_rx_param_wqes(). Enabling the feature again does
not help, as the flag is already set and the reopen is skipped.

Propagate the error, clear the flag and destroy the accel TCP flow
tables again, so that the feature stays disabled and the next attempt
retries the reopen.

Fixes: abed42f9cd80 ("net/mlx5e: Conditionally create async ICOSQ")
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c
index 337201f12895..3cc1213c2f68 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls.c
@@ -139,7 +139,11 @@ int mlx5e_ktls_set_feature_rx(struct net_device *netdev, bool enable)
 		err = mlx5e_accel_fs_tcp_create(priv->fs);
 		if (!err && !priv->ktls_rx_was_enabled) {
 			priv->ktls_rx_was_enabled = true;
-			mlx5e_safe_reopen_channels(priv);
+			err = mlx5e_safe_reopen_channels(priv);
+			if (err) {
+				priv->ktls_rx_was_enabled = false;
+				mlx5e_accel_fs_tcp_destroy(priv->fs);
+			}
 		}
 	} else {
 		mlx5e_accel_fs_tcp_destroy(priv->fs);

base-commit: b71c101bbb9814d163c00234d43c41f0a17907d4
-- 
2.44.0

Re: [PATCH net RESEND] net/mlx5e: kTLS, Fix missing error unwind when enabling RX offload

[netdev-bot+sinfo]

Hi!

This is an automated message. This series looks like a fix, but its
commit messages seem to be missing some information:

 - How the issue was discovered, e.g. hit in production, hit during
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   analysis tool scan.

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Please do not repost the series just to address the above. Instead,
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