diff --git a/drivers/char/apm-emulation.c b/drivers/char/apm-emulation.c
index 4f568cb..033e150 100644
--- a/drivers/char/apm-emulation.c
+++ b/drivers/char/apm-emulation.c
@@ -265,8 +265,8 @@
  *   Only when everyone who has opened /dev/apm_bios with write permission
  *   has acknowledge does the actual suspend happen.
  */
-static int
-apm_ioctl(struct inode * inode, struct file *filp, u_int cmd, u_long arg)
+static long
+apm_ioctl(struct file *filp, u_int cmd, u_long arg)
 {
 	struct apm_user *as = filp->private_data;
 	int err = -EINVAL;
@@ -274,6 +274,7 @@
 	if (!as->suser || !as->writer)
 		return -EPERM;
 
+	lock_kernel();
 	switch (cmd) {
 	case APM_IOC_SUSPEND:
 		mutex_lock(&state_lock);
@@ -334,6 +335,7 @@
 		mutex_unlock(&state_lock);
 		break;
 	}
+	unlock_kernel();
 
 	return err;
 }
@@ -397,7 +399,7 @@
 	.owner		= THIS_MODULE,
 	.read		= apm_read,
 	.poll		= apm_poll,
-	.ioctl		= apm_ioctl,
+	.unlocked_ioctl	= apm_ioctl,
 	.open		= apm_open,
 	.release	= apm_release,
 };