title: How is the bottom of stack determined?
body: <blockquote>
    <p>A stack is a contiguous block of
    memory containing data.  A register
    called the stack pointer (SP) points
    to the top of the stack.  The bottom
    of the  stack is at a fixed address.</p>
  </blockquote>
  
  <p>How is the stack bottom <strong>fixed</strong> by the kernel?</p>