patch 'ethdev: return 0 from dummy queue count' has been queued to stable release 25.11.3

[Kevin Traynor]

Hi,

FYI, your patch has been queued to stable release 25.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 08/01/26. 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/c66596ca17af26dcfc80d1cdfeb97f8bbdfa1fd1

Thanks.

Kevin

---
>From c66596ca17af26dcfc80d1cdfeb97f8bbdfa1fd1 Mon Sep 17 00:00:00 2001
From: Maxime Leroy <maxime at leroys.fr>
Date: Tue, 16 Jun 2026 11:42:58 +0200
Subject: [PATCH] ethdev: return 0 from dummy queue count
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

[ upstream commit dd9a309c32040accd43bac2839cbe0e3376bfd5e ]

The dummy rx_queue_count/tx_queue_count callback returned -ENOTSUP. On a
port that is not started (freshly allocated, or stopped once the fast-path
ops are reset to dummies) there are no packets queued, so the truthful
answer is 0, not an error: querying the count is not an unsupported
operation. This also matches the dummy Rx/Tx burst, which reports 0
packets.

A poll-mode worker checking rte_eth_rx_queue_count() across a concurrent
port stop then sees an empty queue instead of a negative error.

Fixes: 066f3d9cc21c ("ethdev: remove callback checks from fast path")

Suggested-by: Stephen Hemminger <stephen at networkplumber.org>
Signed-off-by: Maxime Leroy <maxime at leroys.fr>
Acked-by: Morten Brørup <mb at smartsharesystems.com>
Acked-by: Stephen Hemminger <stephen at networkplumber.org>
---
 lib/ethdev/ethdev_driver.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/ethdev/ethdev_driver.c b/lib/ethdev/ethdev_driver.c
index 70ddce5bfc..eab5c15d12 100644
--- a/lib/ethdev/ethdev_driver.c
+++ b/lib/ethdev/ethdev_driver.c
@@ -876,5 +876,5 @@ int
 rte_eth_queue_count_dummy(void *queue __rte_unused)
 {
-	return -ENOTSUP;
+	return 0;
 }
 
-- 
2.55.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2026-07-28 16:54:53.416525739 +0100
+++ 0090-ethdev-return-0-from-dummy-queue-count.patch	2026-07-28 16:54:50.847816137 +0100
@@ -1 +1 @@
-From dd9a309c32040accd43bac2839cbe0e3376bfd5e Mon Sep 17 00:00:00 2001
+From c66596ca17af26dcfc80d1cdfeb97f8bbdfa1fd1 Mon Sep 17 00:00:00 2001
@@ -8,0 +9,2 @@
+[ upstream commit dd9a309c32040accd43bac2839cbe0e3376bfd5e ]
+
@@ -20 +21,0 @@
-Cc: stable at dpdk.org