[PATCH] s390: fix locking in __chp_add() and s390_subchannel_remove_chpid()

Fix locking in __chp_add() and s390_subchannel_remove_chpid(): Need to
disable/enable because they are always called from a thread (and not
directly from a machine check...)
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/s390/cio/chsc.c

@@ -232,7 +232,7 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
 		return 0;
 
 	mask = 0x80 >> j;
-	spin_lock(&sch->lock);
+	spin_lock_irq(&sch->lock);
 
 	stsch(sch->schid, &schib);
 	if (!schib.pmcw.dnv)
@@ -281,10 +281,10 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
 	if (sch->driver && sch->driver->verify)
 		sch->driver->verify(&sch->dev);
 out_unlock:
-	spin_unlock(&sch->lock);
+	spin_unlock_irq(&sch->lock);
 	return 0;
 out_unreg:
-	spin_unlock(&sch->lock);
+	spin_unlock_irq(&sch->lock);
 	sch->lpm = 0;
 	if (css_enqueue_subchannel_slow(sch->schid)) {
 		css_clear_subchannel_slow_list();
@@ -652,7 +652,7 @@ __chp_add(struct subchannel_id schid, void *data)
 	if (!sch)
 		/* Check if the subchannel is now available. */
 		return __chp_add_new_sch(schid);
-	spin_lock(&sch->lock);
+	spin_lock_irq(&sch->lock);
 	for (i=0; i<8; i++)
 		if (sch->schib.pmcw.chpid[i] == chp->id) {
 			if (stsch(sch->schid, &sch->schib) != 0) {
@@ -674,7 +674,7 @@ __chp_add(struct subchannel_id schid, void *data)
 	if (sch->driver && sch->driver->verify)
 		sch->driver->verify(&sch->dev);
 
-	spin_unlock(&sch->lock);
+	spin_unlock_irq(&sch->lock);
 	put_device(&sch->dev);
 	return 0;
 }