patch 'net/mlx5: fix NAT64 HW registers calculation' has been queued to stable release 25.11.1

[Kevin Traynor]

Hi,

FYI, your patch has been queued to stable release 25.11.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 03/31/26. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable/commit/dc4757ce8135676a68a372b644dd0584774b522d

Thanks.

Kevin

---
>From dc4757ce8135676a68a372b644dd0584774b522d Mon Sep 17 00:00:00 2001
From: Bing Zhao <bingz at nvidia.com>
Date: Wed, 25 Mar 2026 11:58:26 +0200
Subject: [PATCH] net/mlx5: fix NAT64 HW registers calculation

[ upstream commit 145a94542445005549c64293c79c351aa40a4aa4 ]

mlx5 PMD needs to select a set of 3 HW registers
which will be used to implement NAT64 flow action.
For compatibility reasons one of these registers has to be REG_C_6.
Offending patch introduced a bug to register selection logic.
If REG_C_6 was not available for use,
no registers were selected for NAT64.
So all the registers' information would not be initialized for the
temporary storage of headers information of NAT64.

This patch adds missing logic to use the last 3 available tag registers
in this case, allowing NAT64 flow action to be used.

Fixes: f15535128617 ("net/mlx5: fix NAT64 register selection")

Signed-off-by: Bing Zhao <bingz at nvidia.com>
Acked-by: Dariusz Sosnowski <dsosnowski at nvidia.com>
---
 drivers/net/mlx5/mlx5.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 1488f3c7ea..bc3edae7fc 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1680,4 +1680,10 @@ mlx5_init_hws_flow_tags_registers(struct mlx5_dev_ctx_shared *sh)
 		reg->nat64_regs[1] = reg->hw_avl_tags[j - 2];
 		reg->nat64_regs[2] = reg->hw_avl_tags[j - 1];
+	} else {
+		if (j >= MLX5_FLOW_NAT64_REGS_MAX) {
+			reg->nat64_regs[0] = reg->hw_avl_tags[j - 3];
+			reg->nat64_regs[1] = reg->hw_avl_tags[j - 2];
+			reg->nat64_regs[2] = reg->hw_avl_tags[j - 1];
+		}
 	}
 }
-- 
2.53.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2026-03-27 09:58:26.774167415 +0000
+++ 0021-net-mlx5-fix-NAT64-HW-registers-calculation.patch	2026-03-27 09:58:26.149625508 +0000
@@ -1 +1 @@
-From 145a94542445005549c64293c79c351aa40a4aa4 Mon Sep 17 00:00:00 2001
+From dc4757ce8135676a68a372b644dd0584774b522d Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 145a94542445005549c64293c79c351aa40a4aa4 ]
+
@@ -19 +20,0 @@
-Cc: stable at dpdk.org
@@ -28 +29 @@
-index d9bc5ee197..70f52df78a 100644
+index 1488f3c7ea..bc3edae7fc 100644