54 lines
1.5 KiB
HTML
54 lines
1.5 KiB
HTML
|
<title>Homework: xv6 and Interrupts and Exceptions</title>
|
||
|
|
<html>
|
||
|
|
<head>
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
|
||
|
|
<h1>Homework: xv6 and Interrupts and Exceptions</h1>
|
||
|
|
|
||
|
|
<p>
|
||
|
|
<b>Read</b>: xv6's trapasm.S, trap.c, syscall.c, vectors.S, and usys.S. Skim
|
||
|
|
lapic.c, ioapic.c, and picirq.c
|
||
|
|
|
||
|
|
<p>
|
||
|
|
<b>Hand-In Procedure</b>
|
||
|
|
<p>
|
||
|
|
You are to turn in this homework during lecture. Please
|
||
|
|
write up your answers to the exercises below and hand them in to a
|
||
|
|
6.828 staff member at the beginning of the lecture.
|
||
|
|
<p>
|
||
|
|
|
||
|
|
<b>Introduction</b>
|
||
|
|
|
||
|
|
<p>Try to understand
|
||
|
|
xv6's trapasm.S, trap.c, syscall.c, vectors.S, and usys.S. Skim
|
||
|
|
You will need to consult:
|
||
|
|
|
||
|
|
<p>Chapter 5 of <a href="../readings/ia32/IA32-3.pdf">IA-32 Intel
|
||
|
|
Architecture Software Developer's Manual, Volume 3: System programming
|
||
|
|
guide</a>; you can skip sections 5.7.1, 5.8.2, and 5.12.2. Be aware
|
||
|
|
that terms such as exceptions, traps, interrupts, faults and aborts
|
||
|
|
have no standard meaning.
|
||
|
|
|
||
|
|
<p>Chapter 9 of the 1987 <a href="../readings/i386/toc.htm">i386
|
||
|
|
Programmer's Reference Manual</a> also covers exception and interrupt
|
||
|
|
handling in IA32 processors.
|
||
|
|
|
||
|
|
<p><b>Assignment</b>:
|
||
|
|
|
||
|
|
In xv6, set a breakpoint at the beginning of <code>syscall()</code> to
|
||
|
|
catch the very first system call. What values are on the stack at
|
||
|
|
this point? Turn in the output of <code>print-stack 35</code> at that
|
||
|
|
breakpoint with each value labeled as to what it is (e.g.,
|
||
|
|
saved <code>%ebp</code> for <code>trap</code>,
|
||
|
|
<code>trapframe.eip</code>, etc.).
|
||
|
|
<p>
|
||
|
|
<b>This completes the homework.</b>
|
||
|
|
|
||
|
|
</body>
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|