Re: Kernel testing

Eric.Schenk@dna.lth.se
Mon, 14 Apr 1997 22:12:51 +0200


"Seth M. Landsman" <seth@job.cs.brandeis.edu> writes:
>On 14 Apr 1997, Miguel de Icaza wrote:
>> The test suite then could actually stress test the kernel code without
>> even booting the kernel.
>
> Exactly. It would save a whole lot of problems for many people if
>they could test the integrity of the kernel before they installed it.
>This wouldn't save everyone from installing a kernel that didn't boot, but
>it would save some ...

Note that while this will catch a certain class of errors, it will won't
do much to catch race conditions or broken hardware initializations
which only occur when the kernel is booted live.

If you're kernel won't boot it's often because of a race condition
or some stupid hardware initialization. Still, ex-suiti (is that even a
word?) testing ofvarious critical kernel routines is a good idea,
expecially if the way they are tested is to write a bit of code
that calls the routine and tries to force it to do something wrong.

We can always accumulate such bits of testing code over time as we
spot errors in the kernel. It does take a bit more effort on the part
of developers who must also write new testing when they discover a
kernel bug, but you often end up writing a good bit of such code anyway
to test your theories about what is really going on in the kernel.

The same can be said for collecting bits of code that are used to test
a running kernel.

-- 
Eric Schenk                               www: http://www.dna.lth.se/~erics
Dept. of Comp. Sci., Lund University          email: Eric.Schenk@dna.lth.se
Box 118, S-221 00 LUND, Sweden   fax: +46-46 13 10 21  ph: +46-46 222 96 38