netdev - [PATCH net] Revert "r8169: don't try to disable interrupts if NAPI is, scheduled already"

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: <9b5b6f4c-4f54-4b90-b0b3-8d8023c2e780@gmail.com>
Date: Wed, 15 May 2024 08:18:01 +0200
From: Heiner Kallweit <hkallweit1@...il.com>
To: Eric Dumazet <edumazet@...gle.com>, Paolo Abeni <pabeni@...hat.com>,
 Jakub Kicinski <kuba@...nel.org>, David Miller <davem@...emloft.net>,
 Realtek linux nic maintainers <nic_swsd@...ltek.com>
Cc: "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
 Ken Milmore <ken.milmore@...il.com>
Subject: [PATCH net] Revert "r8169: don't try to disable interrupts if NAPI
 is, scheduled already"

This reverts commit 7274c4147afbf46f45b8501edbdad6da8cd013b9.

Ken reported that RTL8125b can lock up if gro_flush_timeout has the
default value of 20000 and napi_defer_hard_irqs is set to 0.
In this scenario device interrupts aren't disabled, what seems to
trigger some silicon bug under heavy load. I was able to reproduce this
behavior on RTL8168h. Fix this by reverting 7274c4147afb.

Fixes: 7274c4147afb ("r8169: don't try to disable interrupts if NAPI is scheduled already")
Cc: stable@...r.kernel.org
Reported-by: Ken Milmore <ken.milmore@...il.com>
Signed-off-by: Heiner Kallweit <hkallweit1@...il.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 0fc5fe564ae5..69606c8081a3 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4655,10 +4655,8 @@ static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 		rtl_schedule_task(tp, RTL_FLAG_TASK_RESET_PENDING);
 	}
 
-	if (napi_schedule_prep(&tp->napi)) {
-		rtl_irq_disable(tp);
-		__napi_schedule(&tp->napi);
-	}
+	rtl_irq_disable(tp);
+	napi_schedule(&tp->napi);
 out:
 	rtl_ack_events(tp, status);
 
-- 
2.45.0