From 66539255beeb3686e1aa4d20cc419900f5b1e5d2 Mon Sep 17 00:00:00 2001
From: "Sergey Semyonov (Serge)" <ion2@mail.ru>
Date: Thu, 17 Feb 2011 11:28:43 +0000
Subject: [PATCH] ddk: missing chkstk.S

git-svn-id: svn://kolibrios.org@1873 a494cfbc-eb01-0410-851d-a64ba20cac60
---
 drivers/ddk/debug/chkstk.S | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)
 create mode 100644 drivers/ddk/debug/chkstk.S

diff --git a/drivers/ddk/debug/chkstk.S b/drivers/ddk/debug/chkstk.S
new file mode 100644
index 0000000000..cf0a8d0d94
--- /dev/null
+++ b/drivers/ddk/debug/chkstk.S
@@ -0,0 +1,31 @@
+
+.global ___chkstk
+.global __alloca
+
+.section .text
+
+.align 4
+___chkstk:
+__alloca:
+        pushl   %ecx            /* save temp */
+        leal    8(%esp), %ecx   /* point past return addr */
+        subl    %eax, %ecx
+        call *__imp__GetStackBase
+        cmpl    %eax, %ecx      # check low stack limit
+        jb      1f
+
+        movl    %esp, %eax      /* save old stack pointer */
+        movl    %ecx, %esp      /* decrement stack */
+        movl    (%eax), %ecx    /* recover saved temp */
+        movl    4(%eax), %eax   /* recover return address */
+
+        /* Push the return value back.  Doing this instead of just
+           jumping to %eax preserves the cached call-return stack
+           used by most modern processors.  */
+        pushl   %eax
+        ret
+1:
+        int3                    #trap to debugger.
+                                #Oh wait... there is no kernel debugger
+        .ascii "Stack overflow"
+