diff --git a/drivers/isdn/mISDN/layer1.c b/drivers/isdn/mISDN/layer1.c
index ac4aa18c632b..5cc7c001c523 100644
--- a/drivers/isdn/mISDN/layer1.c
+++ b/drivers/isdn/mISDN/layer1.c
@@ -99,12 +99,16 @@ static void
 l1m_debug(struct FsmInst *fi, char *fmt, ...)
 {
 	struct layer1 *l1 = fi->userdata;
+	struct va_format vaf;
 	va_list va;
 
 	va_start(va, fmt);
-	printk(KERN_DEBUG "%s: ", dev_name(&l1->dch->dev.dev));
-	vprintk(fmt, va);
-	printk("\n");
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "%s: %pV\n", dev_name(&l1->dch->dev.dev), &vaf);
+
 	va_end(va);
 }
 
diff --git a/drivers/isdn/mISDN/layer2.c b/drivers/isdn/mISDN/layer2.c
index c97371788764..4ae75053c9d2 100644
--- a/drivers/isdn/mISDN/layer2.c
+++ b/drivers/isdn/mISDN/layer2.c
@@ -95,14 +95,20 @@ static void
 l2m_debug(struct FsmInst *fi, char *fmt, ...)
 {
 	struct layer2 *l2 = fi->userdata;
+	struct va_format vaf;
 	va_list va;
 
 	if (!(*debug & DEBUG_L2_FSM))
 		return;
+
 	va_start(va, fmt);
-	printk(KERN_DEBUG "l2 (sapi %d tei %d): ", l2->sapi, l2->tei);
-	vprintk(fmt, va);
-	printk("\n");
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "l2 (sapi %d tei %d): %pV\n",
+	       l2->sapi, l2->tei, &vaf);
+
 	va_end(va);
 }
 
diff --git a/drivers/isdn/mISDN/tei.c b/drivers/isdn/mISDN/tei.c
index 1b85d9d27496..687c9b6264ab 100644
--- a/drivers/isdn/mISDN/tei.c
+++ b/drivers/isdn/mISDN/tei.c
@@ -79,14 +79,19 @@ static void
 da_debug(struct FsmInst *fi, char *fmt, ...)
 {
 	struct manager	*mgr = fi->userdata;
+	struct va_format vaf;
 	va_list va;
 
 	if (!(*debug & DEBUG_L2_TEIFSM))
 		return;
+
 	va_start(va, fmt);
-	printk(KERN_DEBUG "mgr(%d): ", mgr->ch.st->dev->id);
-	vprintk(fmt, va);
-	printk("\n");
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "mgr(%d): %pV\n", mgr->ch.st->dev->id, &vaf);
+
 	va_end(va);
 }
 
@@ -223,14 +228,20 @@ static void
 tei_debug(struct FsmInst *fi, char *fmt, ...)
 {
 	struct teimgr	*tm = fi->userdata;
+	struct va_format vaf;
 	va_list va;
 
 	if (!(*debug & DEBUG_L2_TEIFSM))
 		return;
+
 	va_start(va, fmt);
-	printk(KERN_DEBUG "sapi(%d) tei(%d): ", tm->l2->sapi, tm->l2->tei);
-	vprintk(fmt, va);
-	printk("\n");
+
+	vaf.fmt = fmt;
+	vaf.va = &va;
+
+	printk(KERN_DEBUG "sapi(%d) tei(%d): %pV\n",
+	       tm->l2->sapi, tm->l2->tei, &vaf);
+
 	va_end(va);
 }