ecs150 Fall 2005: Discussion

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ecs150 Fall 2005Discussion1 Assignment

• Dr. S. Felix Wu
• Computer Science Department
• University of California, Davis
• http//www.cs.ucdavis.edu/wu/
• sfelixwu_at_gmail.com

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Two Parts

• The Programming part
• The tracing Writing part
• /usr/src/sys/
• /usr/src/sys/kern/.c
• /usr/src/sys/sys/proc.h
• /usr/src/sys/i386/i386/.cs

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FreeBSD Installation

• 5.4 CD iso-images on the web site
• Make sure that the CDs are OK
• kernel development package
• If vmware/virtual PC, you can access the CD
  images as virtual CDs.

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Compiling the Kernel

• Before you compile
• Follow the direction in the website
• The MYKERNEL configuration
• /usr/src/sys/i386/compile/MYKERNEL
• make dep
• Only ONCE unless you add new .h dependency
• make all
• make install

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/kernel ? /kernel.old

• On every new kernel installation
• ? KEEP ONE GOOD KERNEL
• /kernel ? /kernel.good
• press 6 to escape and use the boot option to
• boot kernel.good

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KLD

• kldstat
• kldload
• kldunload

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System Entry Vector
fork()
Trap

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System Entry Vector
fork()
Trap
Reserved for loadable system calls

XYZ()
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kldload
fork()
Trap
XYZ()

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kld examples

• See the web link for more info
• helloworld.c
• call.c
• Makefile

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Modifying proc.h

• Add to the zero section.

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One trick ? struct proc

• PID ? struct proc

struct proc p1 p1 pfind(uap-gtpid) if
(p1) p1-gttickets uap-gttickets PROC_UNLOCK(p
1)