diff --git a/net/irda/irnet/irnet.h b/net/irda/irnet/irnet.h
index b001c361ad30976ff3a1de5bfe80fe2f0142b6f9..bccf4d0059f0a6a629bbd5913015b0453caaa5e9 100644
--- a/net/irda/irnet/irnet.h
+++ b/net/irda/irnet/irnet.h
@@ -241,6 +241,7 @@
 #include <linux/module.h>
 
 #include <linux/kernel.h>
+#include <linux/smp_lock.h>
 #include <linux/skbuff.h>
 #include <linux/tty.h>
 #include <linux/proc_fs.h>
diff --git a/net/irda/irnet/irnet_ppp.c b/net/irda/irnet/irnet_ppp.c
index e0eab5927c4f434d6210711525ac9b14ba34599e..e84a70dd346b7e48a350502699238286d6cf2f21 100644
--- a/net/irda/irnet/irnet_ppp.c
+++ b/net/irda/irnet/irnet_ppp.c
@@ -479,6 +479,7 @@ dev_irnet_open(struct inode *	inode,
   ap = kzalloc(sizeof(*ap), GFP_KERNEL);
   DABORT(ap == NULL, -ENOMEM, FS_ERROR, "Can't allocate struct irnet...\n");
 
+  lock_kernel();
   /* initialize the irnet structure */
   ap->file = file;
 
@@ -500,6 +501,7 @@ dev_irnet_open(struct inode *	inode,
     {
       DERROR(FS_ERROR, "Can't setup IrDA link...\n");
       kfree(ap);
+      unlock_kernel();
       return err;
     }
 
@@ -510,6 +512,7 @@ dev_irnet_open(struct inode *	inode,
   file->private_data = ap;
 
   DEXIT(FS_TRACE, " - ap=0x%p\n", ap);
+  unlock_kernel();
   return 0;
 }