From 565cae1a2fcac990ec6d3a32555f3220d1033232 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Wed, 16 Sep 2020 16:15:39 +0200
Subject: [PATCH 237/327] net: Dequeue in dev_cpu_dead() without the lock

Upstream uses skb_dequeue() to acquire lock of `input_pkt_queue'. The reason is
to synchronize against a remote CPU which still thinks that the CPU is online
enqueues packets to this CPU.
There are no guarantees that the packet is enqueued before the callback is run,
it just hope.
RT however complains about an not initialized lock because it uses another lock
for `input_pkt_queue' due to the IRQ-off nature of the context.

Use the unlocked dequeue version for `input_pkt_queue'.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 net/core/dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index af31fb7d7555..0cc123cf6fea 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -11008,7 +11008,7 @@ static int dev_cpu_dead(unsigned int oldcpu)
 		netif_rx_ni(skb);
 		input_queue_head_incr(oldsd);
 	}
-	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
+	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
 		netif_rx_ni(skb);
 		input_queue_head_incr(oldsd);
 	}
-- 
2.49.0

