diff --git a/configs/open1788/kernel/up_userspace.c b/configs/open1788/kernel/up_userspace.c
index 3947af1cdad..2263bc3f5e6 100644
--- a/configs/open1788/kernel/up_userspace.c
+++ b/configs/open1788/kernel/up_userspace.c
@@ -44,7 +44,6 @@
 #include <nuttx/userspace.h>
 #include <nuttx/wqueue.h>
 #include <nuttx/mm.h>
-#include <nuttx/sched.h>
 
 #if defined(CONFIG_NUTTX_KERNEL) && !defined(__KERNEL__)
 
@@ -102,13 +101,19 @@ const struct userspace_s userspace __attribute__ ((section (".userspace"))) =
   .us_bssstart      = (uintptr_t)&_sbss,
   .us_bssend        = (uintptr_t)&_ebss,
 
-  /* Task/thread startup stubs */
+  /* Task/thread startup routines */
 
   .task_startup     = task_startup,
 #ifndef CONFIG_DISABLE_PTHREAD
   .pthread_startup  = pthread_startup,
 #endif
 
+  /* Signal handler trampoline */
+
+#ifndef CONFIG_DISABLE_SIGNALS
+  .signal_handler   = signal_handler,
+#endif
+
   /* Memory manager entry points (declared in include/nuttx/mm.h) */
 
   .mm_initialize    = umm_initialize,
diff --git a/configs/open1788/knsh/defconfig b/configs/open1788/knsh/defconfig
index b8d36e6fd2a..addfd82ada9 100755
--- a/configs/open1788/knsh/defconfig
+++ b/configs/open1788/knsh/defconfig
@@ -344,7 +344,7 @@ CONFIG_IDLETHREAD_STACKSIZE=1024
 CONFIG_USERMAIN_STACKSIZE=2048
 CONFIG_PTHREAD_STACK_MIN=256
 CONFIG_PTHREAD_STACK_DEFAULT=2048
-CONFIG_SYS_RESERVED=6
+CONFIG_SYS_RESERVED=8
 
 #
 # Device Drivers
diff --git a/configs/sam3u-ek/kernel/up_userspace.c b/configs/sam3u-ek/kernel/up_userspace.c
index ee61d1b692b..484cdc2d020 100644
--- a/configs/sam3u-ek/kernel/up_userspace.c
+++ b/configs/sam3u-ek/kernel/up_userspace.c
@@ -101,13 +101,19 @@ const struct userspace_s userspace __attribute__ ((section (".userspace"))) =
   .us_bssstart      = (uintptr_t)&_sbss,
   .us_bssend        = (uintptr_t)&_ebss,
 
-  /* Task/thread startup stubs */
+  /* Task/thread startup routines */
 
   .task_startup     = task_startup,
 #ifndef CONFIG_DISABLE_PTHREAD
   .pthread_startup  = pthread_startup,
 #endif
 
+  /* Signal handler trampoline */
+
+#ifndef CONFIG_DISABLE_SIGNALS
+  .signal_handler   = signal_handler,
+#endif
+
   /* Memory manager entry points (declared in include/nuttx/mm.h) */
 
   .mm_initialize    = umm_initialize,
diff --git a/configs/sam3u-ek/knsh/defconfig b/configs/sam3u-ek/knsh/defconfig
index 9bdb33004a8..71c646083ba 100755
--- a/configs/sam3u-ek/knsh/defconfig
+++ b/configs/sam3u-ek/knsh/defconfig
@@ -249,7 +249,7 @@ CONFIG_IDLETHREAD_STACKSIZE=1024
 CONFIG_USERMAIN_STACKSIZE=2048
 CONFIG_PTHREAD_STACK_MIN=256
 CONFIG_PTHREAD_STACK_DEFAULT=2048
-CONFIG_SYS_RESERVED=6
+CONFIG_SYS_RESERVED=8
 
 #
 # Device Drivers