[PATCH 4.4 32/36] fakelb: fix schedule while atomic

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alexander Aring <aar@xxxxxxxxxxxxxx>

commit bdca1fd9a6df745857e23c6056494b7fe062b4e6 upstream.

This patch changes the spinlock to mutex for the available fakelb phy
list. When holding the spinlock the ieee802154_unregister_hw is called
which holding the rtnl_mutex, in that case we get a "BUG: sleeping function
called from invalid context" error. We simple change the spinlock to
mutex which allows to hold the rtnl lock there.

Signed-off-by: Alexander Aring <aar@xxxxxxxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/ieee802154/fakelb.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/drivers/net/ieee802154/fakelb.c
+++ b/drivers/net/ieee802154/fakelb.c
@@ -30,7 +30,7 @@
 static int numlbs = 2;
 
 static LIST_HEAD(fakelb_phys);
-static DEFINE_SPINLOCK(fakelb_phys_lock);
+static DEFINE_MUTEX(fakelb_phys_lock);
 
 static LIST_HEAD(fakelb_ifup_phys);
 static DEFINE_RWLOCK(fakelb_ifup_phys_lock);
@@ -180,9 +180,9 @@ static int fakelb_add_one(struct device
 	if (err)
 		goto err_reg;
 
-	spin_lock(&fakelb_phys_lock);
+	mutex_lock(&fakelb_phys_lock);
 	list_add_tail(&phy->list, &fakelb_phys);
-	spin_unlock(&fakelb_phys_lock);
+	mutex_unlock(&fakelb_phys_lock);
 
 	return 0;
 
@@ -214,10 +214,10 @@ static int fakelb_probe(struct platform_
 	return 0;
 
 err_slave:
-	spin_lock(&fakelb_phys_lock);
+	mutex_lock(&fakelb_phys_lock);
 	list_for_each_entry_safe(phy, tmp, &fakelb_phys, list)
 		fakelb_del(phy);
-	spin_unlock(&fakelb_phys_lock);
+	mutex_unlock(&fakelb_phys_lock);
 	return err;
 }
 
@@ -225,10 +225,10 @@ static int fakelb_remove(struct platform
 {
 	struct fakelb_phy *phy, *tmp;
 
-	spin_lock(&fakelb_phys_lock);
+	mutex_lock(&fakelb_phys_lock);
 	list_for_each_entry_safe(phy, tmp, &fakelb_phys, list)
 		fakelb_del(phy);
-	spin_unlock(&fakelb_phys_lock);
+	mutex_unlock(&fakelb_phys_lock);
 	return 0;
 }