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Re: Re[2]: general protection: 4f00



> If the program is ran as root it can crash the system in a thousand
> different ways. (e.g: "rm -fr /"). Besides, every OS can have fatal buffer
> overflows, including Linux. At least on an i386.

I don't really understand why "rm -fr /" should crash the kernel. Also,
programs are usually executed in user mode, that is - if it crashes, the
control is passed to exception handlers, process is wiped out and the
kernel continues. No process should cause kernel fault. If it does, it may
be useful to read /usr/src/linux/Documentation/oops-tracing.txt.

You also possibly are mixing root privilegies and user/kernel mode
privilegies. Root is irrelevant with regards to processor - it's only
tells to kernel that this process has some rights, and according to this
allows or doesn't allow it to execute various operations. 

> 
> Maybe VMS or MVS or other real-time or mainframe OSes do something to
> ensure this thing cannot happen. I'm not sure that Pentium processors
> offer enough functionality to prevent this, or that Linux is designed with

Yes. Intel processor have exception handling mechanisms. Linux uses them
AFAIK.

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