diff --git a/drivers/macintosh/via-pmu.c b/drivers/macintosh/via-pmu.c
index d6365a9..d524dc2 100644
--- a/drivers/macintosh/via-pmu.c
+++ b/drivers/macintosh/via-pmu.c
@@ -18,6 +18,7 @@
  *
  */
 #include <stdarg.h>
+#include <linux/smp_lock.h>
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
@@ -2047,6 +2048,7 @@
 	pp->rb_get = pp->rb_put = 0;
 	spin_lock_init(&pp->lock);
 	init_waitqueue_head(&pp->wait);
+	lock_kernel();
 	spin_lock_irqsave(&all_pvt_lock, flags);
 #if defined(CONFIG_INPUT_ADBHID) && defined(CONFIG_PMAC_BACKLIGHT)
 	pp->backlight_locker = 0;
@@ -2054,6 +2056,7 @@
 	list_add(&pp->list, &all_pmu_pvt);
 	spin_unlock_irqrestore(&all_pvt_lock, flags);
 	file->private_data = pp;
+	unlock_kernel();
 	return 0;
 }