add some comments regarding relocation of kernel during configuration

kernel/inithma.c

@@ -305,16 +305,19 @@ VOID FAR * HMAalloc(COUNT bytesToAllocate)
 
 unsigned CurrentKernelSegment = 0;
 
+/* relocate segment with HMA_TEXT code group */
 void MoveKernel(unsigned NewKernelSegment)
 {
   UBYTE FAR *HMADest;
   UBYTE FAR *HMASource;
   unsigned len;
   unsigned jmpseg = CurrentKernelSegment;
 
+  /* if the first time called, initialize to end of HMA_TEXT code group segment */  
   if (CurrentKernelSegment == 0)
     CurrentKernelSegment = FP_SEG(_HMATextEnd);
 
+  /* if already relocated into HMA, nothing to do */
   if (CurrentKernelSegment == 0xffff)
     return;
 
@@ -324,6 +327,8 @@ void MoveKernel(unsigned NewKernelSegment)
 
   len = (FP_OFF(_HMATextEnd) | 0x000f) - (FP_OFF(_HMATextStart) & 0xfff0);
 
+  /* HMA doesn't start until a paragraph into 0xffff segment */
+  /* HMA begins with VDISK header to mark area is used */
   if (NewKernelSegment == 0xffff)
   {
     HMASource += HMAOFFSET;

kernel/main.c

@@ -305,7 +305,14 @@ STATIC void init_kernel(void)
   /* Init oem hook - returns memory size in KB    */
   ram_top = init_oem();
 
-  /* move kernel to high conventional RAM, just below the init code */
+  /* Note: HMA_TEXT and init code already moved higher in
+     conventional memory by startup code, however, we still
+	 need to adjust any references to new location.  So use
+	 current CS as that is where we were moved to and perform
+	 any fixups needed.  Note this will also re-copy the 
+	 HMA_TEXT segment, so be sure not to overwrite it prior
+	 to the MoveKernel() call.  Kernel moved to around 8F??:0000
+  */
 #ifdef __WATCOMC__
   lpTop = MK_FP(_CS, 0);
 #else