s390/qdio: lock device while installing IRQ handler

During setup, qdio takes control of the presented ccw device and replaces the device's IRQ handler with its own. To avoid any interference with conccurent activity on the device, this should be done while holding the device's lock. Signed-off-by: Julian Wiedmann <[email protected]> Reviewed-by: Benjamin Block <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]>
sfionov · Apr 10, 2018 · 7eee12b · 7eee12b
1 parent 8928632
commit 7eee12b
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/s390/cio/qdio_setup.c b/drivers/s390/cio/qdio_setup.c
@@ -507,8 +507,10 @@ int qdio_setup_irq(struct qdio_initialize *init_data)
 	irq_ptr->aqueue = *ciw;
 
 	/* set new interrupt handler */
+	spin_lock_irq(get_ccwdev_lock(irq_ptr->cdev));
 	irq_ptr->orig_handler = init_data->cdev->handler;
 	init_data->cdev->handler = qdio_int_handler;
+	spin_unlock_irq(get_ccwdev_lock(irq_ptr->cdev));
 	return 0;
 out_err:
 	qdio_release_memory(irq_ptr);