diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index b6817eab23..309fd05966 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -3349,3 +3349,15 @@
 	* configs/*/nxwm/defconfig and sched/task_exithook.c: Fixes for
 	  bugs that crept in during recent changes.  (Submitted by Max
 	  Holtzberg).
+	* arch/arm/include/armv7-m/irq.h:  Fix a critical bug in irqsave().
+	  It looks like sometimes the compile will re-order some instructions
+	  inapproapriately.  This end result is that interrupts will get
+	  stuff off.
+	* drivers/mtd/w25.c:  Beginning of a driver for the Windbond SPI
+	  FLASH family (W25x16, W25x32, and W25x64).  The initial check-in
+	  is basically just the SST25 driver with some name changes.
+	* arch/arm/include/armv7-m/irq.h and arch/arm/src/stm32/stm32_spi.c:
+	  Back out the last change in irq.h.  It is (most likely) fine the
+	  way it was.  The really interrupt related problem was in stm32_spi.c:
+	  When SPI3 is not enabled, then the irqrestore() falls in the
+	  else clause.
diff --git a/nuttx/arch/arm/include/armv7-m/irq.h b/nuttx/arch/arm/include/armv7-m/irq.h
index 950ce80ca4..b6306d3390 100644
--- a/nuttx/arch/arm/include/armv7-m/irq.h
+++ b/nuttx/arch/arm/include/armv7-m/irq.h
@@ -129,6 +129,64 @@ struct xcptcontext
 
 #ifndef __ASSEMBLY__
 
+/* Disable IRQs */
+
+static inline void irqdisable(void) __attribute__((always_inline));
+static inline void irqdisable(void)
+{
+  __asm__ __volatile__ ("\tcpsid  i\n");
+}
+
+/* Save the current primask state & disable IRQs */
+
+static inline irqstate_t irqsave(void) __attribute__((always_inline));
+static inline irqstate_t irqsave(void)
+{
+  unsigned short primask;
+
+  /* Return the current value of primask register and set
+   * bit 0 of the primask register to disable interrupts
+   */
+
+  __asm__ __volatile__
+    (
+     "\tmrs    %0, primask\n"
+     "\tcpsid  i\n"
+     : "=r" (primask)
+     :
+     : "memory");
+
+  return primask;
+}
+
+/* Enable IRQs */
+
+static inline void irqenable(void) __attribute__((always_inline));
+static inline void irqenable(void)
+{
+  __asm__ __volatile__ ("\tcpsie  i\n");
+}
+
+/* Restore saved primask state */
+
+static inline void irqrestore(irqstate_t primask) __attribute__((always_inline));
+static inline void irqrestore(irqstate_t primask)
+{
+  /* If bit 0 of the primask is 0, then we need to restore
+   * interupts.
+   */
+
+  __asm__ __volatile__
+    (
+      "\ttst    %0, #1\n"
+      "\tbne    1f\n"
+      "\tcpsie  i\n"
+      "1:\n"
+      :
+      : "r" (primask)
+      : "memory");
+}
+
 /* Get/set the primask register */
 
 static inline uint8_t getprimask(void) __attribute__((always_inline));
@@ -145,39 +203,6 @@ static inline uint8_t getprimask(void)
   return (uint8_t)primask;
 }
 
-/* Disable IRQs */
-
-static inline void irqdisable(void) __attribute__((always_inline));
-static inline void irqdisable(void)
-{
-  __asm__ __volatile__ ("\tcpsid  i\n");
-}
-
-/* Save the current primask state & disable IRQs */
-
-static inline irqstate_t irqsave(void) __attribute__((always_inline));
-static inline irqstate_t irqsave(void)
-{
-  /* Return the current value of primask register (before disabling) */
-
-  uint8_t primask = getprimask();
-
-  /* Then set bit 0 of the primask register to disable interrupts */
-
-  irqdisable();
-  return primask;
-}
-
-/* Enable IRQs */
-
-static inline void irqenable(void) __attribute__((always_inline));
-static inline void irqenable(void)
-{
-  __asm__ __volatile__ ("\tcpsie  i\n");
-}
-
-/* Restore saved primask state */
-
 static inline void setprimask(uint32_t primask) __attribute__((always_inline));
 static inline void setprimask(uint32_t primask)
 {
@@ -189,19 +214,6 @@ static inline void setprimask(uint32_t primask)
       : "memory");
 }
 
-static inline void irqrestore(irqstate_t primask) __attribute__((always_inline));
-static inline void irqrestore(irqstate_t primask)
-{
-  /* If bit 0 of the primask is 0, then we need to restore
-   * interrupts.
-   */
-
-  if ((primask & 1) == 0)
-    {
-      setprimask(primask);
-    }
-}
-
 /* Get/set the basepri register */
 
 static inline uint8_t getbasepri(void) __attribute__((always_inline));
diff --git a/nuttx/arch/arm/src/stm32/stm32_spi.c b/nuttx/arch/arm/src/stm32/stm32_spi.c
index 2d907bfca7..8de698cd5a 100644
--- a/nuttx/arch/arm/src/stm32/stm32_spi.c
+++ b/nuttx/arch/arm/src/stm32/stm32_spi.c
@@ -1431,7 +1431,12 @@ FAR struct spi_dev_s *up_spiinitialize(int port)
           spi_portinitialize(priv);
         }
     }
+  else
 #endif
+    {
+      spidbg("ERROR: Unsupported SPI port: %d\n", port);
+      return NULL;
+    }
 
   irqrestore(flags);
   return (FAR struct spi_dev_s *)priv;