[3.19.y-ckt stable] Patch "net: dp83640: fix improper double spin locking." has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    net: dp83640: fix improper double spin locking.

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt2.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 43d3b2f06d6b55345eac00185462c40280ac4383 Mon Sep 17 00:00:00 2001
From: Richard Cochran <richardcochran at gmail.com>
Date: Mon, 25 May 2015 11:55:45 +0200
Subject: net: dp83640: fix improper double spin locking.

[ Upstream commit adbe088f6f8b0b7701fe07f51fe6f2bd602a6665 ]

A pair of nested spin locks was introduced in commit 63502b8d0
"dp83640: Fix receive timestamp race condition".

Unfortunately the 'flags' parameter was reused for the inner lock,
clobbering the originally saved IRQ state.  This patch fixes the issue
by changing the inner lock to plain spin_lock without irqsave.

Signed-off-by: Richard Cochran <richardcochran at gmail.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/phy/dp83640.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/dp83640.c b/drivers/net/phy/dp83640.c
index 4f3cf1b..c5789cd 100644
--- a/drivers/net/phy/dp83640.c
+++ b/drivers/net/phy/dp83640.c
@@ -845,7 +845,7 @@ static void decode_rxts(struct dp83640_private *dp83640,
 	list_del_init(&rxts->list);
 	phy2rxts(phy_rxts, rxts);

-	spin_lock_irqsave(&dp83640->rx_queue.lock, flags);
+	spin_lock(&dp83640->rx_queue.lock);
 	skb_queue_walk(&dp83640->rx_queue, skb) {
 		struct dp83640_skb_info *skb_info;

@@ -860,7 +860,7 @@ static void decode_rxts(struct dp83640_private *dp83640,
 			break;
 		}
 	}
-	spin_unlock_irqrestore(&dp83640->rx_queue.lock, flags);
+	spin_unlock(&dp83640->rx_queue.lock);

 	if (!shhwtstamps)
 		list_add_tail(&rxts->list, &dp83640->rxts);
--
1.9.1