From 431d6549eb78cbd4180d8e876532e8de47bc85ff Mon Sep 17 00:00:00 2001
From: Grant Likely <grant.likely@secretlab.ca>
Date: Sat, 9 Feb 2013 09:41:49 +0000
Subject: [PATCH] --- yaml --- r: 358769 b: refs/heads/master c:
 362432aed5e5b497a8cf7b20c268ba71df93c045 h: refs/heads/master i:   358767:
 b24c169fd45a2eef9a8927859d4e1e0cd0537e90 v: v3

---
 [refs]                       |  2 +-
 trunk/drivers/gpio/gpiolib.c | 12 +++++++++---
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 2452ae7cbc2f..302860cf7466 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6c0b4e6c85d085bd92966bc2b8da73e2d7f35929
+refs/heads/master: 362432aed5e5b497a8cf7b20c268ba71df93c045
diff --git a/trunk/drivers/gpio/gpiolib.c b/trunk/drivers/gpio/gpiolib.c
index 5050693dcc35..4b3f388bcc6d 100644
--- a/trunk/drivers/gpio/gpiolib.c
+++ b/trunk/drivers/gpio/gpiolib.c
@@ -2053,29 +2053,35 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 
 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
 {
+	unsigned long flags;
 	struct gpio_chip *chip = NULL;
 	loff_t index = *pos;
 
-	/* REVISIT this isn't locked against gpio_chip removal ... */
-
 	s->private = "";
 
+	spin_lock_irqsave(&gpio_lock, flags);
 	list_for_each_entry(chip, &gpio_chips, list)
-		if (index-- == 0)
+		if (index-- == 0) {
+			spin_unlock_irqrestore(&gpio_lock, flags);
 			return chip;
+		}
+	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	return NULL;
 }
 
 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
+	unsigned long flags;
 	struct gpio_chip *chip = v;
 	void *ret = NULL;
 
+	spin_lock_irqsave(&gpio_lock, flags);
 	if (list_is_last(&chip->list, &gpio_chips))
 		ret = NULL;
 	else
 		ret = list_entry(chip->list.next, struct gpio_chip, list);
+	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	s->private = "\n";
 	++*pos;