netdev - [PATCH] net: netdev_queue: netdev_txq_completed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240112-netdev_queue-v1-1-102c2d57e20a@pengutronix.de>
Date: Fri, 12 Jan 2024 17:13:14 +0100
From: Marc Kleine-Budde <mkl@...gutronix.de>
To: "David S. Miller" <davem@...emloft.net>, 
 Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, 
 Paolo Abeni <pabeni@...hat.com>, Herbert Xu <herbert@...dor.apana.org.au>
Cc: kernel@...gutronix.de, netdev@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Marc Kleine-Budde <mkl@...gutronix.de>
Subject: [PATCH] net: netdev_queue: netdev_txq_completed_mb(): fix wake
 condition

netif_txq_try_stop() uses "get_desc >= start_thrs" as the check for
the call to netif_tx_start_queue().

Use ">=" i netdev_txq_completed_mb(), too.

Fixes: c91c46de6bbc ("net: provide macros for commonly copied lockless queue stop/wake code")
Signed-off-by: Marc Kleine-Budde <mkl@...gutronix.de>
---
Hello,

I'm currently converting a networking driver with a TX-FIFO depth of
1 (CAN device with lots of errata :/) to the netdev_queue.h helpers
and stumbled over an off-by-one error on __netif_txq_completed_wake().

regards,
Marc
---
 include/net/netdev_queues.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index d68b0a483431..8b8ed4e13d74 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -128,7 +128,7 @@ netdev_txq_completed_mb(struct netdev_queue *dev_queue,
 		netdev_txq_completed_mb(txq, pkts, bytes);		\
 									\
 		_res = -1;						\
-		if (pkts && likely(get_desc > start_thrs)) {		\
+		if (pkts && likely(get_desc >= start_thrs)) {		\
 			_res = 1;					\
 			if (unlikely(netif_tx_queue_stopped(txq)) &&	\
 			    !(down_cond)) {				\

---
base-commit: 907ee6681788556b9ade3ad0a1f6f4aea192399c
change-id: 20240112-netdev_queue-e91686f5fece

Best regards,
-- 
Marc Kleine-Budde <mkl@...gutronix.de>