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diff --git a/test/geekos_test_vm/src/geekos/tss.c b/test/geekos_test_vm/src/geekos/tss.c
new file mode 100644
index 0000000..2cdb968
--- /dev/null
+++ b/test/geekos_test_vm/src/geekos/tss.c
@@ -0,0 +1,85 @@
+/*
+ * x86 TSS data structure and routines
+ * Copyright (c) 2001,2004 David H. Hovemeyer <daveho@cs.umd.edu>
+ * $Revision: 1.1 $
+ * 
+ * This is free software.  You are permitted to use,
+ * redistribute, and modify it as specified in the file "COPYING".
+ */
+
+/*
+ * Source: _Protected Mode Software Architecture_ by Tom Shanley,
+ * ISBN 020155447X.
+ */
+
+#include <geekos/kassert.h>
+#include <geekos/defs.h>
+#include <geekos/gdt.h>
+#include <geekos/segment.h>
+#include <geekos/string.h>
+#include <geekos/tss.h>
+
+#include <geekos/debug.h>
+
+/*
+ * We use one TSS in GeekOS.
+ */
+static struct TSS s_theTSS;
+
+// JRL: why??? Should just call Alloc_Page(), otherwise we have dependencies all over the place
+//static struct TSS *s_theTSS = (struct TSS *) TSS_LOCATION;
+
+static struct Segment_Descriptor *s_tssDesc;
+static ushort_t s_tssSelector;
+
+static void __inline__ Load_Task_Register(void)
+{
+    /* Critical: TSS must be marked as not busy */
+    s_tssDesc->type = 0x09;
+
+    /* Load the task register */
+    __asm__ __volatile__ (
+	"ltr %0"
+	:
+	: "a" (s_tssSelector)
+    );
+}
+
+/*
+ * Initialize the kernel TSS.  This must be done after the memory and
+ * GDT initialization, but before the scheduler is started.
+ */
+void Init_TSS(void)
+{
+  PrintBoth("Initializing TSS\n");
+
+    s_tssDesc = Allocate_Segment_Descriptor();
+    KASSERT(s_tssDesc != 0);
+
+    memset(&s_theTSS, '\0', sizeof(struct TSS));
+    Init_TSS_Descriptor(s_tssDesc, &s_theTSS);
+
+    s_tssSelector = Selector(0, true, Get_Descriptor_Index(s_tssDesc));
+
+    Load_Task_Register();
+}
+
+/*
+ * Set kernel stack pointer.
+ * This should be called before switching to a new
+ * user process, so that interrupts occurring while executing
+ * in user mode will be delivered on the correct stack.
+ */
+void Set_Kernel_Stack_Pointer(ulong_t esp0)
+{
+    s_theTSS.ss0 = KERNEL_DS;
+    s_theTSS.esp0 = esp0;
+
+    /*
+     * NOTE: I read on alt.os.development that it is necessary to
+     * reload the task register after modifying a TSS.
+     * I haven't verified this in the IA32 documentation,
+     * but there is certainly no harm in being paranoid.
+     */
+    Load_Task_Register();
+}