From ed7aa30e861510043f602b39f460c90aba792776 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Wed, 20 Jun 2018 21:31:20 +0200
Subject: [PATCH] net: usb: r8152: use irqsave() in USB's complete callback
Git-commit: ed7aa30e861510043f602b39f460c90aba792776
Patch-mainline: v4.19-rc1
References: bsc#1119749

The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/usb/r8152.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index 86f7196f9d91..c08c0d633407 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -1252,6 +1252,7 @@ static void read_bulk_callback(struct urb *urb)
 	int status = urb->status;
 	struct rx_agg *agg;
 	struct r8152 *tp;
+	unsigned long flags;
 
 	agg = urb->context;
 	if (!agg)
@@ -1281,9 +1282,9 @@ static void read_bulk_callback(struct urb *urb)
 		if (urb->actual_length < ETH_ZLEN)
 			break;
 
-		spin_lock(&tp->rx_lock);
+		spin_lock_irqsave(&tp->rx_lock, flags);
 		list_add_tail(&agg->list, &tp->rx_done);
-		spin_unlock(&tp->rx_lock);
+		spin_unlock_irqrestore(&tp->rx_lock, flags);
 		napi_schedule(&tp->napi);
 		return;
 	case -ESHUTDOWN:
@@ -1311,6 +1312,7 @@ static void write_bulk_callback(struct urb *urb)
 	struct net_device *netdev;
 	struct tx_agg *agg;
 	struct r8152 *tp;
+	unsigned long flags;
 	int status = urb->status;
 
 	agg = urb->context;
@@ -1332,9 +1334,9 @@ static void write_bulk_callback(struct urb *urb)
 		stats->tx_bytes += agg->skb_len;
 	}
 
-	spin_lock(&tp->tx_lock);
+	spin_lock_irqsave(&tp->tx_lock, flags);
 	list_add_tail(&agg->list, &tp->tx_free);
-	spin_unlock(&tp->tx_lock);
+	spin_unlock_irqrestore(&tp->tx_lock, flags);
 
 	usb_autopm_put_interface_async(tp->intf);
 
-- 
2.19.2