[S390] cio: ensure proper locking during device recognition
Device recognition needs to be started with the ccw device lock
held to prevent race conditions between I/O starting and interrupt
reception.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 7ad6bfb..afa362c 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -488,7 +488,9 @@
{
/* Do device recognition, if needed. */
if (cdev->private->state == DEV_STATE_BOXED) {
+ spin_lock_irq(cdev->ccwlock);
ccw_device_recognition(cdev);
+ spin_unlock_irq(cdev->ccwlock);
wait_event(cdev->private->wait_q,
cdev->private->flags.recog_done);
if (cdev->private->state != DEV_STATE_OFFLINE)
