diff --git a/os/ports/GCC/ARMCMx/chcore_v6m.c b/os/ports/GCC/ARMCMx/chcore_v6m.c
index 162348385..1e4371c10 100644
--- a/os/ports/GCC/ARMCMx/chcore_v6m.c
+++ b/os/ports/GCC/ARMCMx/chcore_v6m.c
@@ -116,16 +116,9 @@ void _port_switch_from_isr(void) {
 #if !defined(__DOXYGEN__)
 __attribute__((naked))
 #endif
-void port_switch(Thread *ntp, Thread *otp) {
+void _port_switch(Thread *ntp, Thread *otp) {
   register struct intctx *r13 asm ("r13");
 
-  /* Stack overflow check, if enabled.*/
-#if CH_DBG_ENABLE_STACK_CHECK
-  if ((void *)(r13 - 1) < (void *)(otp + 1))
-    asm volatile ("movs    r0, #0                               \n\t"
-                  "b       chDbgPanic");
-#endif /* CH_DBG_ENABLE_STACK_CHECK */
-
   PUSH_CONTEXT(r13);
 
   otp->p_ctx.r13 = r13;
diff --git a/os/ports/GCC/ARMCMx/chcore_v6m.h b/os/ports/GCC/ARMCMx/chcore_v6m.h
index d495e1f5c..518eba855 100644
--- a/os/ports/GCC/ARMCMx/chcore_v6m.h
+++ b/os/ports/GCC/ARMCMx/chcore_v6m.h
@@ -88,7 +88,7 @@ struct intctx {
  *          reduce this value to zero when compiling with optimizations.
  */
 #ifndef IDLE_THREAD_STACK_SIZE
-#define IDLE_THREAD_STACK_SIZE      8
+#define IDLE_THREAD_STACK_SIZE      16
 #endif
 
 /**
@@ -206,11 +206,32 @@ struct intctx {
 #define port_wait_for_interrupt()
 #endif
 
+/**
+ * @brief   Performs a context switch between two threads.
+ * @details This is the most critical code in any port, this function
+ *          is responsible for the context switch between 2 threads.
+ * @note    The implementation of this code affects <b>directly</b> the context
+ *          switch performance so optimize here as much as you can.
+ *
+ * @param[in] ntp       the thread to be switched in
+ * @param[in] otp       the thread to be switched out
+ */
+#if !defined(CH_DBG_ENABLE_STACK_CHECK) || defined(__DOXYGEN__)
+#define port_switch(ntp, otp) _port_switch(ntp, otp)
+#else
+#define port_switch(ntp, otp) {                                             \
+  register struct intctx *r13 asm ("r13");                                  \
+  if ((void *)(r13 - 1) < (void *)(otp + 1))                                \
+    chDbgPanic("stack overflow");                                           \
+  _port_switch(ntp, otp);                                                   \
+}
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
   void port_halt(void);
-  void port_switch(Thread *ntp, Thread *otp);
+  void _port_switch(Thread *ntp, Thread *otp);
   void _port_irq_epilogue(regarm_t lr);
   void _port_switch_from_isr(void);
   void _port_thread_start(void);
diff --git a/os/ports/IAR/ARMCMx/chcore_v6m.h b/os/ports/IAR/ARMCMx/chcore_v6m.h
index 39d19d390..2b8ae6266 100644
--- a/os/ports/IAR/ARMCMx/chcore_v6m.h
+++ b/os/ports/IAR/ARMCMx/chcore_v6m.h
@@ -88,7 +88,7 @@ struct intctx {
  *          reduce this value to zero when compiling with optimizations.
  */
 #ifndef IDLE_THREAD_STACK_SIZE
-#define IDLE_THREAD_STACK_SIZE      8
+#define IDLE_THREAD_STACK_SIZE      16
 #endif
 
 /**
diff --git a/os/ports/RVCT/ARMCMx/chcore_v6m.h b/os/ports/RVCT/ARMCMx/chcore_v6m.h
index 51d8a4d1c..a02709dfe 100644
--- a/os/ports/RVCT/ARMCMx/chcore_v6m.h
+++ b/os/ports/RVCT/ARMCMx/chcore_v6m.h
@@ -88,7 +88,7 @@ struct intctx {
  *          reduce this value to zero when compiling with optimizations.
  */
 #ifndef IDLE_THREAD_STACK_SIZE
-#define IDLE_THREAD_STACK_SIZE      8
+#define IDLE_THREAD_STACK_SIZE      16
 #endif
 
 /**
diff --git a/readme.txt b/readme.txt
index 6feb78802..b9c4fd9c0 100644
--- a/readme.txt
+++ b/readme.txt
@@ -69,6 +69,9 @@
 *****************************************************************************
 
 *** 2.2.3 ***
+- FIX: Fixed insufficient idle thread stack in Cortex-M0-GCC port
+  (bug 3226671).
+- FIX: Fixed stack checking in Cortex-M0-GCC port (bug 3226657).
 - FIX: Fixed wrong checks in PAL driver (bug 3224681).
 - FIX: Fixed wrong checks in I/O Queues (bug 3219197).
 - FIX: Fixed invalid assertion in adcConvert() (bug 3205410).