diff --git a/sdk/xtdk/amd64/ketypes.h b/sdk/xtdk/amd64/ketypes.h
index fe83506..f322c41 100644
--- a/sdk/xtdk/amd64/ketypes.h
+++ b/sdk/xtdk/amd64/ketypes.h
@@ -133,6 +133,9 @@
 #define KTRAP_FRAME_ALIGN                 0x10
 #define KTRAP_FRAME_SIZE                  sizeof(KTRAP_FRAME)
 
+/* Return address size pushed by 'call' instruction */
+#define KRETURN_ADDRESS_SIZE              0x8
+
 /* Size of legacy 387 registers */
 #define SIZE_OF_80387_REGISTERS           80
 
diff --git a/sdk/xtdk/i686/ketypes.h b/sdk/xtdk/i686/ketypes.h
index ccab6ff..14e65a4 100644
--- a/sdk/xtdk/i686/ketypes.h
+++ b/sdk/xtdk/i686/ketypes.h
@@ -162,6 +162,9 @@
 /* Number of supported extensions */
 #define MAXIMUM_SUPPORTED_EXTENSION       512
 
+/* Return address size pushed by 'call' instruction */
+#define KRETURN_ADDRESS_SIZE              0x4
+
 /* Size of 387 registers */
 #define SIZE_OF_80387_REGISTERS           80
 #define SIZE_OF_FX_REGISTERS              128
diff --git a/xtoskrnl/ke/amd64/krnlinit.c b/xtoskrnl/ke/amd64/krnlinit.c
index b411f02..6054701 100644
--- a/xtoskrnl/ke/amd64/krnlinit.c
+++ b/xtoskrnl/ke/amd64/krnlinit.c
@@ -105,6 +105,6 @@ KepSwitchBootStack(IN ULONG_PTR Stack)
                  "jmp KepStartKernel\n"
                  :
                  : "m" (Stack),
-                   "i" (FLOATING_SAVE_AREA_SIZE | KEXCEPTION_FRAME_SIZE | KSWITCH_FRAME_SIZE),
+                   "i" (FLOATING_SAVE_AREA_SIZE | KEXCEPTION_FRAME_SIZE | KSWITCH_FRAME_SIZE | KRETURN_ADDRESS_SIZE),
                    "p" (KepStartKernel));
 }
diff --git a/xtoskrnl/ke/i686/krnlinit.c b/xtoskrnl/ke/i686/krnlinit.c
index 4a3b69d..900cb54 100644
--- a/xtoskrnl/ke/i686/krnlinit.c
+++ b/xtoskrnl/ke/i686/krnlinit.c
@@ -106,7 +106,7 @@ KepSwitchBootStack(IN ULONG_PTR Stack)
                  "jmp _KepStartKernel@0\n"
                  :
                  : "m" (Stack),
-                   "i" (KTRAP_FRAME_ALIGN | KTRAP_FRAME_SIZE | NPX_FRAME_SIZE),
+                   "i" (KTRAP_FRAME_ALIGN | KTRAP_FRAME_SIZE | NPX_FRAME_SIZE | KRETURN_ADDRESS_SIZE),
                    "i" (CR0_EM | CR0_MP | CR0_TS),
                    "p" (KepStartKernel));
 }