patch 'net/memif: fix Tx count on invalid interrupt FD' has been queued to stable release 24.11.9

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 24.11.9

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/07/26. 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/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/7cfb19e9180cf808372d48eb7818949d4e8a3aa2

Thanks.

Luca Boccassi

---
>From 7cfb19e9180cf808372d48eb7818949d4e8a3aa2 Mon Sep 17 00:00:00 2001
From: Sriram Yagnaraman <sriram.yagnaraman at ericsson.com>
Date: Fri, 16 Oct 2026 21:58:56 +0200
Subject: [PATCH] net/memif: fix Tx count on invalid interrupt FD

[ upstream commit 320b42d65a23d06898ec4c59acc6f2e5fec43170 ]

eth_memif_tx_zc() returns uint16_t but did "return -1" when the
interrupt FD was invalid, so the caller saw 65535 packets sent after
ring->head had already been published. The FD can legitimately be -1:
memif_init_queues() only warns and continues when eventfd() fails. Skip
the kick when the FD is invalid, as eth_memif_tx() does, and return the
real count.

Fixes: aedd054c5c2a ("drivers: check interrupt file descriptor validity")

Suggested-by: Stephen Hemminger <stephen at networkplumber.org>
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman at ericsson.com>
---
 drivers/net/memif/rte_eth_memif.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
index 856dc165d50..c9474a525e1 100644
--- a/drivers/net/memif/rte_eth_memif.c
+++ b/drivers/net/memif/rte_eth_memif.c
@@ -1252,11 +1252,9 @@ no_free_slots:
 	rte_atomic_store_explicit(&ring->head, slot, rte_memory_order_release);
 
 	/* Send interrupt, if enabled. */
-	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
+	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0 &&
+	    rte_intr_fd_get(mq->intr_handle) >= 0) {
 		uint64_t a = 1;
-		if (rte_intr_fd_get(mq->intr_handle) < 0)
-			return -1;
-
 		ssize_t size = write(rte_intr_fd_get(mq->intr_handle),
 				     &a, sizeof(a));
 		if (unlikely(size < 0)) {
-- 
2.47.3

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2026-11-05 16:42:48.120632696 +0000
+++ 0083-net-memif-fix-Tx-count-on-invalid-interrupt-FD.patch	2026-11-05 16:42:45.017063655 +0000
@@ -1 +1 @@
-From 320b42d65a23d06898ec4c59acc6f2e5fec43170 Mon Sep 17 00:00:00 2001
+From 7cfb19e9180cf808372d48eb7818949d4e8a3aa2 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 320b42d65a23d06898ec4c59acc6f2e5fec43170 ]
+
@@ -14 +15,0 @@
-Cc: stable at dpdk.org
@@ -23 +24 @@
-index cdf77d77b0..0680dc3947 100644
+index 856dc165d50..c9474a525e1 100644
@@ -26 +27 @@
-@@ -1254,11 +1254,9 @@ no_free_slots:
+@@ -1252,11 +1252,9 @@ no_free_slots: