User-Mode Linux for Apple PowerPC G5

[Stefan Bruda]

At 11:12 -0500 on 2005-1-17 Derick Centeno wrote:
 >
 > This is exactly what is so enticing AND confusing.  Linux is strong
 > enough to take abuse, and now someone has created a space within
 > Linux where the abuse can occur safely?

Two words: kernel mode.  When one hacks into the kernel one would not
want to abuse a production machine with her hacks.  I have seen it
first hand, about one year ago I supervised a student of mine who
worked on process and memory quota support for Linux as his honours
project.  User space Linux allowed them (and myself) to hack the
kernel safely (no less than the memory management subsystem, mind
you), to debug the hacks, and to test the results.  Needless to say,
the user space machine did crash a considerable number fo times during
the process.

I guess that the same user space needs arise when one tests
administrative tools/suid-ed programs--you would not want to give them
full access to a production machine in the testing phase.

Stefan

-- 
``There's no use trying, one can't believe impossible things.''
``I daresay you haven't had much practice.  When I was your age, I
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    --Lewis Carroll, Through the Looking-Glass