patch 'net/netvsc: fix resource leaks on MTU change' 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 03/23/26. 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/71f2a8a935c61cb89c94cf30c1e1f2c9d0446800

Thanks.

Kevin

---
>From 71f2a8a935c61cb89c94cf30c1e1f2c9d0446800 Mon Sep 17 00:00:00 2001
From: Long Li <longli at microsoft.com>
Date: Tue, 3 Mar 2026 12:54:08 -0800
Subject: [PATCH] net/netvsc: fix resource leaks on MTU change

[ upstream commit 980b54aaa21e92382e11f55d316e5ba38de990c6 ]

hn_dev_mtu_set() has several resource management bugs:

1. Calls rte_free(hv->channels[0]) without rte_vmbus_chan_close()
   first, skipping the VMBus close protocol.

2. Does not free hv->primary->rxbuf_info before hn_detach(), causing
   hn_nvs_conn_rxbuf() in hn_reinit() to leak the old allocation.

3. Does not call hn_chim_uninit()/hn_chim_init() around the
   detach/reinit sequence, leaving a stale chimney bitmap that may
   not match the new chim_cnt.

Fix all three issues.

Fixes: 45c83603087e ("net/netvsc: support MTU set")

Signed-off-by: Long Li <longli at microsoft.com>
---
 drivers/net/netvsc/hn_ethdev.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/net/netvsc/hn_ethdev.c b/drivers/net/netvsc/hn_ethdev.c
index a6ed0356bc..61c90bf16e 100644
--- a/drivers/net/netvsc/hn_ethdev.c
+++ b/drivers/net/netvsc/hn_ethdev.c
@@ -1245,12 +1245,21 @@ hn_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 		return ret;
 
+	/* Free chimney bitmap and rxbuf_info before NVS detach */
+	hn_chim_uninit(dev);
+	rte_free(hv->primary->rxbuf_info);
+	hv->primary->rxbuf_info = NULL;
+
 	/* Release channel resources */
 	hn_detach(hv);
 
 	/* Close any secondary vmbus channels */
-	for (i = 1; i < hv->num_queues; i++)
+	for (i = 1; i < hv->num_queues; i++) {
 		rte_vmbus_chan_close(hv->channels[i]);
+		hv->channels[i] = NULL;
+	}
+	hv->num_queues = 1;
 
 	/* Close primary vmbus channel */
+	rte_vmbus_chan_close(hv->channels[0]);
 	rte_free(hv->channels[0]);
 
@@ -1276,9 +1285,12 @@ hn_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 	}
 
+	hv->primary->chan = hv->channels[0];
 	rte_vmbus_set_latency(hv->vmbus, hv->channels[0], hv->latency);
 
 	ret = hn_reinit(dev, mtu);
-	if (!ret)
+	if (!ret) {
+		hn_chim_init(dev);
 		goto out;
+	}
 
 	/* In case of error, attempt to restore original MTU */
@@ -1286,4 +1298,6 @@ hn_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 	if (ret)
 		PMD_DRV_LOG(ERR, "Restoring original MTU failed for netvsc");
+	else
+		hn_chim_init(dev);
 
 	ret = hn_vf_mtu_set(dev, orig_mtu);
-- 
2.53.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2026-03-19 10:01:08.998245285 +0000
+++ 0066-net-netvsc-fix-resource-leaks-on-MTU-change.patch	2026-03-19 10:01:07.124689205 +0000
@@ -1 +1 @@
-From 980b54aaa21e92382e11f55d316e5ba38de990c6 Mon Sep 17 00:00:00 2001
+From 71f2a8a935c61cb89c94cf30c1e1f2c9d0446800 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 980b54aaa21e92382e11f55d316e5ba38de990c6 ]
+
@@ -21 +22,0 @@
-Cc: stable at dpdk.org