Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FD21390CAD for ; Wed, 9 Sep 2026 17:52:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788976326; cv=none; b=G4pC3f4COe1xM2nrKaKJ6CreDwGhCTsJLv6vWvU7VSiwxjImGMav1qbnyErozdE704Uz2tvg6SmmXfnuL39Clhzv5BJGCOrmzlqgv10i374hlRrwhJu6xFsoOBwnnEwFTekWun5QE31Fih0+JkUkkemXVCG2wh8rCPKp2evpNFc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788976326; c=relaxed/simple; bh=QvsmRrnmXOAxyfeFpt3bfdpneffrGRWwmP6hYtVuhpU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GAA28tI3I1PBrkVySQt68y+b+lUAzMf2tI5rCXfiVwRuO8kYlntB7FBvaN4ghkxAAq1nlOo2kpaddIAITeU0nG0/IThBr9CiOJiM0J06pWSXKLBWDyfUVsuBWAkdpsJkQoyRSO6Buv067DWw5959XvwfUrVyG/LLmqsHAnUuwCw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mwPwPP0T; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mwPwPP0T" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1AC31F0089B; Wed, 9 Sep 2026 17:52:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788976324; bh=WEOMcHYKxt/fs/Dso3LtANlXGLygm0wdkeRSK0SV4vI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mwPwPP0TlBdD4T59/3twAIGHHGG4xVjazmgCWDbPpx1Spq15IXqPQHlu8O2iiUfqv +n5Hcl/kDzEO005ylhGcQJNeTWk4dZZbGsDQ/q0ZsskQJstuwqUfOsMal8Qw9PLEBP dZq3yCOtzNncQSdbk8JjuGGhXoEZVF2pZD0Q8jS/yCKuTtvrovhfDTrUGmVHsJJniS rEQv2MLnQwfoBCjlAZHD/Fl6SWclUMnBpldAslk1sRqN/3I/bwR3EdauAYGPlbEs1A bSuuee+2MeOwiH8snPeFooqFdR/x5MntWOTuIPGqBLS76C4GQLLkSvFde1lBGHZ5Sq h3B34YJ/8LnBA== From: Sasha Levin To: stable@vger.kernel.org Cc: Breno Leitao , Nicolai Buchwitz , Jason Xing , Paolo Abeni , Sasha Levin Subject: [PATCH 5.15.y 2/2] net: fix spurious TX timeout after dev_activate() Date: Wed, 9 Sep 2026 13:52:01 -0400 Message-ID: <20260909175201.3360823-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909175201.3360823-1-sashal@kernel.org> References: <2026090352-dealmaker-grope-80e1@gregkh> <20260909175201.3360823-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Breno Leitao [ Upstream commit 82aeed2400786bd3f79d88cb8b8f42e6127e5923 ] While debugging another issue today, I found out that my TX queue is reported as stopped for 4294907392 ms (49.7 days), on a machine that had been up for four minutes. bnxt_en 0002:01:00.0 eth0: NETDEV WATCHDOG: CPU: 28: transmit queue 23 timed out 4294907392 ms 4294907392 is not an elapsed time. It is the value of jiffies at that moment: INITIAL_JIFFIES is 4294667296, which leaves jiffies 59 seconds short of wrapping. dev_activate() runs transition_one_qdisc() over every TX queue, which resets trans_start to 0, and then stamps only queue 0 through netif_trans_update(). Stamp jiffies instead. A queue stopped across dev_activate() now gets a full watchdog_timeo of grace, and is still reported if it is stopped that long. Fixes: 9b36627acecd ("net: remove dev->trans_start") Cc: stable@vger.kernel.org Signed-off-by: Breno Leitao Reviewed-by: Nicolai Buchwitz Reviewed-by: Jason Xing Link: https://patch.msgid.link/20260825-trans_start-v2-1-286b4d6d70cb@debian.org Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/sched/sch_generic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index f0036693df9e6..2861473a118a5 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1175,7 +1175,7 @@ static void transition_one_qdisc(struct net_device *dev, rcu_assign_pointer(dev_queue->qdisc, new_qdisc); if (need_watchdog_p) { - WRITE_ONCE(dev_queue->trans_start, 0); + WRITE_ONCE(dev_queue->trans_start, jiffies); *need_watchdog_p = 1; } } -- 2.53.0