diff --git a/arch/arm/include/armv7-m/irq.h b/arch/arm/include/armv7-m/irq.h
index f63fadbc49..39210b07ac 100644
--- a/arch/arm/include/armv7-m/irq.h
+++ b/arch/arm/include/armv7-m/irq.h
@@ -292,7 +292,7 @@ static inline irqstate_t up_irq_save(void)
 static inline void up_irq_enable(void) inline_function;
 static inline void up_irq_enable(void)
 {
-  setbasepri(0);
+  setbasepri(NVIC_SYSH_PRIORITY_MIN);
   __asm__ __volatile__ ("\tcpsie  i\n");
 }
 
diff --git a/arch/arm/src/arm/up_sigdeliver.c b/arch/arm/src/arm/up_sigdeliver.c
index 29176429f3..1fb7b1eeff 100644
--- a/arch/arm/src/arm/up_sigdeliver.c
+++ b/arch/arm/src/arm/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/arm/up_sigdeliver.c
  *
- *   Copyright (C) 2007-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -113,9 +113,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_CPSR]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/arm/src/armv6-m/up_sigdeliver.c b/arch/arm/src/armv6-m/up_sigdeliver.c
index c2b3e8675e..ed045faf38 100644
--- a/arch/arm/src/armv6-m/up_sigdeliver.c
+++ b/arch/arm/src/armv6-m/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/armv6-m/up_sigdeliver.c
  *
- *   Copyright (C) 2013-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013-2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -54,18 +54,6 @@
 
 #ifndef CONFIG_DISABLE_SIGNALS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -122,9 +110,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore((uint8_t)regs[REG_PRIMASK]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signal */
 
diff --git a/arch/arm/src/armv7-a/arm_sigdeliver.c b/arch/arm/src/armv7-a/arm_sigdeliver.c
index 5d89583282..861e065f7d 100644
--- a/arch/arm/src/armv7-a/arm_sigdeliver.c
+++ b/arch/arm/src/armv7-a/arm_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/armv7-a/arm_sigdeliver.c
  *
- *   Copyright (C) 2013, 2015-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013, 2015-2016, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -101,9 +101,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  leave_critical_section(regs[REG_CPSR]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signal */
 
diff --git a/arch/arm/src/armv7-m/up_sigdeliver.c b/arch/arm/src/armv7-m/up_sigdeliver.c
index 5aff11499c..6ecd0ee66d 100644
--- a/arch/arm/src/armv7-m/up_sigdeliver.c
+++ b/arch/arm/src/armv7-m/up_sigdeliver.c
@@ -1,7 +1,8 @@
 /****************************************************************************
  * arch/arm/src/armv7-m/up_sigdeliver.c
  *
- *   Copyright (C) 2009-2010, 2013-2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2010, 2013-2016, 2018 Gregory Nutt. All rights
+ *     reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -109,12 +110,12 @@ void up_sigdeliver(void)
   sigdeliver           = (sig_deliver_t)rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-#ifdef CONFIG_ARMV7M_USEBASEPRI
-  leave_critical_section((uint8_t)regs[REG_BASEPRI]);
-#else
-  leave_critical_section((uint16_t)regs[REG_PRIMASK]);
+  up_irq_enable();
 #endif
 
   /* Deliver the signal */
diff --git a/arch/arm/src/armv7-r/arm_sigdeliver.c b/arch/arm/src/armv7-r/arm_sigdeliver.c
index 280a5ef9c7..be24c2c01c 100644
--- a/arch/arm/src/armv7-r/arm_sigdeliver.c
+++ b/arch/arm/src/armv7-r/arm_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/armv7-r/arm_sigdeliver.c
  *
- *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -101,9 +101,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_CPSR]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/avr/src/avr/up_sigdeliver.c b/arch/avr/src/avr/up_sigdeliver.c
index c73460793e..7b33c79afd 100644
--- a/arch/avr/src/avr/up_sigdeliver.c
+++ b/arch/avr/src/avr/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/avr/src/avr/up_sigdeliver.c
  *
- *   Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -104,9 +104,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_SREG]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/avr/src/avr32/up_sigdeliver.c b/arch/avr/src/avr32/up_sigdeliver.c
index 811e4b031c..1ef31dfb61 100644
--- a/arch/avr/src/avr32/up_sigdeliver.c
+++ b/arch/avr/src/avr32/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/avr/src/avr32/up_sigdeliver.c
  *
- *   Copyright (C) 2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -104,9 +104,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_SR]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/mips/src/mips32/up_sigdeliver.c b/arch/mips/src/mips32/up_sigdeliver.c
index bf8f8e1708..4c986d4235 100644
--- a/arch/mips/src/mips32/up_sigdeliver.c
+++ b/arch/mips/src/mips32/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/mips/src/mips32/up_sigdeliver.c
  *
- *   Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -114,9 +114,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore((irqstate_t)regs[REG_STATUS]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/misoc/src/lm32/lm32_sigdeliver.c b/arch/misoc/src/lm32/lm32_sigdeliver.c
index f889691469..8b96ae47d7 100644
--- a/arch/misoc/src/lm32/lm32_sigdeliver.c
+++ b/arch/misoc/src/lm32/lm32_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/misoc/src/lm32/lm32_sigdeliver.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -101,9 +101,13 @@ void lm32_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore((irqstate_t)regs[REG_INT_CTX]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/renesas/src/m16c/m16c_sigdeliver.c b/arch/renesas/src/m16c/m16c_sigdeliver.c
index a56448c36b..199bb6f752 100644
--- a/arch/renesas/src/m16c/m16c_sigdeliver.c
+++ b/arch/renesas/src/m16c/m16c_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/renesas/src/m16c/m16c_sigdeliver.c
  *
- *   Copyright (C) 2009-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -115,9 +115,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(rtcb->xcp.saved_flg);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/renesas/src/sh1/sh1_sigdeliver.c b/arch/renesas/src/sh1/sh1_sigdeliver.c
index 8662cb47c5..5e1e286eca 100644
--- a/arch/renesas/src/sh1/sh1_sigdeliver.c
+++ b/arch/renesas/src/sh1/sh1_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/renesas/src/common/up_sigdeliver.c
  *
- *   Copyright (C) 2008-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -114,9 +114,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_SR] & 0x000000f0);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/risc-v/src/rv32im/up_sigdeliver.c b/arch/risc-v/src/rv32im/up_sigdeliver.c
index 6d57a2b4a3..73ecbcb227 100644
--- a/arch/risc-v/src/rv32im/up_sigdeliver.c
+++ b/arch/risc-v/src/rv32im/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/risc-v/src/rv32im/up_sigdeliver.c
  *
- *   Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  *   Modified for RISC-V:
@@ -60,18 +60,6 @@
 
 #ifndef CONFIG_DISABLE_SIGNALS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -119,9 +107,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore((irqstate_t)regs[REG_INT_CTX]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/x86/src/i486/up_sigdeliver.c b/arch/x86/src/i486/up_sigdeliver.c
index b6ec9a09d5..9805d3be90 100644
--- a/arch/x86/src/i486/up_sigdeliver.c
+++ b/arch/x86/src/i486/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/x86/src/i486/up_sigdeliver.c
  *
- *   Copyright (C) 2011, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -54,18 +54,6 @@
 
 #ifndef CONFIG_DISABLE_SIGNALS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -113,9 +101,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_EFLAGS]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/xtensa/src/common/xtensa_sigdeliver.c b/arch/xtensa/src/common/xtensa_sigdeliver.c
index ec6e6c56dd..9aed74990b 100644
--- a/arch/xtensa/src/common/xtensa_sigdeliver.c
+++ b/arch/xtensa/src/common/xtensa_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/xtensa/src/common/arm_sigdeliver.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2016, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -100,9 +100,13 @@ void xtensa_sig_deliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[REG_PS]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/z16/src/common/up_sigdeliver.c b/arch/z16/src/common/up_sigdeliver.c
index f9429d041b..4e40bc6a35 100644
--- a/arch/z16/src/common/up_sigdeliver.c
+++ b/arch/z16/src/common/up_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/z16/src/common/up_sigdeliver.c
  *
- *   Copyright (C) 2008-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -103,12 +103,13 @@ void up_sigdeliver(void)
   sigdeliver           = (sig_deliver_t)rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  if ((regs[REG_FLAGS] & Z16F_CNTRL_FLAGS_IRQE) != 0)
-    {
-       EI();
-    }
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/z80/src/ez80/ez80_sigdeliver.c b/arch/z80/src/ez80/ez80_sigdeliver.c
index 694b3c0186..de2d60a358 100644
--- a/arch/z80/src/ez80/ez80_sigdeliver.c
+++ b/arch/z80/src/ez80/ez80_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/z80/src/ez80/ez80_sigdeliver.c
  *
- *   Copyright (C) 2008-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -114,9 +114,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[XCPT_I]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/z80/src/z180/z180_sigdeliver.c b/arch/z80/src/z180/z180_sigdeliver.c
index 3a67b345f8..75ffb20dc6 100644
--- a/arch/z80/src/z180/z180_sigdeliver.c
+++ b/arch/z80/src/z180/z180_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/z80/src/z180/z180_sigdeliver.c
  *
- *   Copyright (C) 2012, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -113,9 +113,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[XCPT_I]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/z80/src/z8/z8_sigdeliver.c b/arch/z80/src/z8/z8_sigdeliver.c
index b6abac296a..57aeb48d65 100644
--- a/arch/z80/src/z8/z8_sigdeliver.c
+++ b/arch/z80/src/z8/z8_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/z80/src/z8/z8_sigdeliver.c
  *
- *   Copyright (C) 2008-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,14 +52,6 @@
 
 #ifndef CONFIG_DISABLE_SIGNALS
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
@@ -128,9 +120,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[XCPT_IRQCTL]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */
 
diff --git a/arch/z80/src/z80/z80_sigdeliver.c b/arch/z80/src/z80/z80_sigdeliver.c
index 232eb4be98..e173f92357 100644
--- a/arch/z80/src/z80/z80_sigdeliver.c
+++ b/arch/z80/src/z80/z80_sigdeliver.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/z80/src/z80/z80_sigdeliver.c
  *
- *   Copyright (C) 2007-2010, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2010, 2015, 2018 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -113,9 +113,13 @@ void up_sigdeliver(void)
   sigdeliver           = rtcb->xcp.sigdeliver;
   rtcb->xcp.sigdeliver = NULL;
 
-  /* Then restore the task interrupt state. */
+#ifndef CONFIG_SUPPRESS_INTERRUPTS
+  /* Then make sure that interrupts are enabled.  Signal handlers must always
+   * run with interrupts enabled.
+   */
 
-  up_irq_restore(regs[XCPT_I]);
+  up_irq_enable();
+#endif
 
   /* Deliver the signals */