diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 925feda6a6d9e0a238f4ef12c0233facf9dff458..9fdbe865dc41b305f2575c23e53d8c922d4c8620 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -2333,7 +2333,13 @@ struct target_flock {
     short l_whence;
     abi_long l_start;
     abi_long l_len;
+#if defined(TARGET_MIPS)
+    abi_long l_sysid;
+#endif
     int l_pid;
+#if defined(TARGET_MIPS)
+    abi_long pad[4];
+#endif
 };
 
 struct target_flock64 {