diff --git a/conts/libl4/include/l4lib/arch-arm/syslib.h b/conts/libl4/include/l4lib/arch-arm/syslib.h
index dc52b7a..5811499 100644
--- a/conts/libl4/include/l4lib/arch-arm/syslib.h
+++ b/conts/libl4/include/l4lib/arch-arm/syslib.h
@@ -305,6 +305,9 @@ static inline void *l4_map_helper(void *phys, int npages)
 	struct task_ids ids;
 	void *virt = l4_new_virtual(npages);
 
+	if (!phys)
+		BUG();
+
 	l4_getid(&ids);
 	l4_map(phys, virt, npages, MAP_USR_RW_FLAGS, ids.tid);
 	return virt;
diff --git a/src/api/space.c b/src/api/space.c
index 786f37e..a860c26 100644
--- a/src/api/space.c
+++ b/src/api/space.c
@@ -25,6 +25,7 @@ int sys_map(unsigned long phys, unsigned long virt, unsigned long npages,
 	return -EINVAL;
 
 found:
+	printk("%s (%d) Mapping from 0x%lx to 0x%lxp, %lu pages\n", __FUNCTION__, tid, phys, virt, npages);
 	add_mapping_pgd(phys, virt, npages << PAGE_BITS, flags, TASK_PGD(target));
 
 	return 0;
diff --git a/src/arch/arm/exception.c b/src/arch/arm/exception.c
index 19034f6..29686df 100644
--- a/src/arch/arm/exception.c
+++ b/src/arch/arm/exception.c
@@ -19,7 +19,7 @@
 #include INC_SUBARCH(mm.h)
 
 /* Abort debugging conditions */
-#define DEBUG_ABORTS
+//#define DEBUG_ABORTS
 #if defined (DEBUG_ABORTS)
 #define dbg_abort(...)	dprintk(__VA_ARGS__)
 #else