Add support for run time stack checking for the STM32. From David Sidrane

arch/arm/src/armv7-m/Kconfig

@@ -65,6 +65,18 @@ config ARMV7M_OABI_TOOLCHAIN
 		Most of the older buildroot toolchains are OABI and are named
 		arm-nuttx-elf- vs. arm-nuttx-eabi-
 
+config ARMV7M_STACKCHECK
+	bool "Stack for stack overflow on each function call"
+	default n
+	depends on ARCH_CHIP_STM32
+	---help---
+		This check uses R10 to check for a stack overflow within each function
+		call. This has performances and code size impacts, but it will be able to
+		catch hard to find stack overflows.
+
+		Currently only available only for the STM32 architecture.  The changes
+		are not complex and patches for other architectures will be accepted.
+
 config ARMV7M_ITMSYSLOG
 	bool "ITM SYSLOG support"
 	default n

arch/arm/src/armv7-m/up_initialstate.c

@@ -93,6 +93,16 @@ void up_initial_state(struct tcb_s *tcb)
 
   xcp->regs[REG_SP]      = (uint32_t)tcb->adj_stack_ptr;
 
+#ifdef CONFIG_ARMV7M_STACKCHECK
+  /* Set the stack limit value */
+
+  xcp->regs[REG_R10]     = (uint32_t)tcb->stack_alloc_ptr + 64;
+
+  /* Fill the stack with a watermark value */
+
+  memset(tcb->stack_alloc_ptr, 0xff, tcb->adj_stack_size);
+#endif
+
   /* Save the task entry point (stripping off the thumb bit) */
 
   xcp->regs[REG_PC]      = (uint32_t)tcb->start & ~1;

arch/arm/src/stm32/Make.defs

@@ -54,6 +54,10 @@ CMN_CSRCS += up_schedulesigaction.c up_sigdeliver.c up_stackframe.c
 CMN_CSRCS += up_systemreset.c up_unblocktask.c up_usestack.c up_doirq.c
 CMN_CSRCS += up_hardfault.c up_svcall.c up_vfork.c
 
+ifeq ($(CONFIG_ARMV7M_STACKCHECK),y)
+CMN_CSRCS += up_stackcheck.c
+endif
+
 ifeq ($(CONFIG_ARMV7M_CMNVECTOR),y)
 CMN_ASRCS += up_exception.S
 CMN_CSRCS += up_vectors.c

arch/arm/src/stm32/stm32_start.c

@@ -2,7 +2,7 @@
  * arch/arm/src/stm32/stm32_start.c
  * arch/arm/src/chip/stm32_start.c
  *
- *   Copyright (C) 2009, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2011-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -88,6 +88,16 @@ static void go_os_start(void *pv, unsigned int nbytes)
 #  define showprogress(c)
 #endif
 
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+#ifdef CONFIG_ARMV7M_STACKCHECK
+/* we need to get r10 set before we can allow instrumentation calls */
+
+void __start(void) __attribute__ ((no_instrument_function));
+#endif
+
 /****************************************************************************
  * Name: stm32_fpuconfig
  *
@@ -235,7 +245,13 @@ void __start(void)
   const uint32_t *src;
   uint32_t *dest;
 
-  /* Configure the uart so that we can get debug output as soon as possible */
+#ifdef CONFIG_ARMV7M_STACKCHECK
+  /* Set the stack limit before we attempt to call any functions */
+
+  __asm__ volatile ("sub r10, sp, %0" : : "r" (CONFIG_IDLETHREAD_STACKSIZE - 64) : );
+#endif
+
+  /* Configure the UART so that we can get debug output as soon as possible */
 
   stm32_clockconfig();
   stm32_fpuconfig();