diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
index 610f91b285..ee5907330f 100644
--- a/bsd-user/mmap.c
+++ b/bsd-user/mmap.c
@@ -42,6 +42,11 @@ void mmap_unlock(void)
     }
 }
 
+bool have_mmap_lock(void)
+{
+    return mmap_lock_count > 0 ? true : false;
+}
+
 /* Grab lock to make sure things are in a consistent state after fork().  */
 void mmap_fork_start(void)
 {
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index cb624e4acc..4d36ee38f7 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -369,6 +369,7 @@ void tlb_fill(CPUState *cpu, target_ulong addr, MMUAccessType access_type,
 #if defined(CONFIG_USER_ONLY)
 void mmap_lock(void);
 void mmap_unlock(void);
+bool have_mmap_lock(void);
 
 static inline tb_page_addr_t get_page_addr_code(CPUArchState *env1, target_ulong addr)
 {
diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index ffd099dfe7..61685bf79e 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -41,6 +41,11 @@ void mmap_unlock(void)
     }
 }
 
+bool have_mmap_lock(void)
+{
+    return mmap_lock_count > 0 ? true : false;
+}
+
 /* Grab lock to make sure things are in a consistent state after fork().  */
 void mmap_fork_start(void)
 {
diff --git a/translate-all.c b/translate-all.c
index f35522e377..5aded3d3bd 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -31,6 +31,7 @@
 #include "tcg.h"
 #if defined(CONFIG_USER_ONLY)
 #include "qemu.h"
+#include "exec/exec-all.h"
 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 #include <sys/param.h>
 #if __FreeBSD_version >= 700104
@@ -58,6 +59,7 @@
 
 /* #define DEBUG_TB_INVALIDATE */
 /* #define DEBUG_TB_FLUSH */
+/* #define DEBUG_LOCKING */
 /* make various TB consistency checks */
 /* #define DEBUG_TB_CHECK */
 
@@ -66,6 +68,28 @@
 #undef DEBUG_TB_CHECK
 #endif
 
+/* Access to the various translations structures need to be serialised via locks
+ * for consistency. This is automatic for SoftMMU based system
+ * emulation due to its single threaded nature. In user-mode emulation
+ * access to the memory related structures are protected with the
+ * mmap_lock.
+ */
+#ifdef DEBUG_LOCKING
+#define DEBUG_MEM_LOCKS 1
+#else
+#define DEBUG_MEM_LOCKS 0
+#endif
+
+#ifdef CONFIG_SOFTMMU
+#define assert_memory_lock() do { /* nothing */ } while (0)
+#else
+#define assert_memory_lock() do {               \
+        if (DEBUG_MEM_LOCKS) {                  \
+            g_assert(have_mmap_lock());         \
+        }                                       \
+    } while (0)
+#endif
+
 #define SMC_BITMAP_USE_THRESHOLD 10
 
 typedef struct PageDesc {
@@ -173,6 +197,23 @@ void tb_lock_reset(void)
 #endif
 }
 
+#ifdef DEBUG_LOCKING
+#define DEBUG_TB_LOCKS 1
+#else
+#define DEBUG_TB_LOCKS 0
+#endif
+
+#ifdef CONFIG_SOFTMMU
+#define assert_tb_lock() do { /* nothing */ } while (0)
+#else
+#define assert_tb_lock() do {               \
+        if (DEBUG_TB_LOCKS) {               \
+            g_assert(have_tb_lock);         \
+        }                                   \
+    } while (0)
+#endif
+
+
 static TranslationBlock *tb_find_pc(uintptr_t tc_ptr);
 
 void cpu_gen_init(void)