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Re: psdatabase file in /boot

>>> psdatabase is responsible for the WCHAN column of the output of "ps
>>> -l", so your system will boot. Without psdatabase, you will get
>>> numbers in this column instead of routine names.
>>What if I recompiled my kernel, changing some kernel config options
>>in the process, but failed to run `psupdate'?
>Then you'd get strange information in WCHAN, for a start.  I don't
>have the source for ps handy, but I expect that it hits a hash table
>created from psdatabase, and you see GIGO.  I doubt, knowing the
>coding standards, that ps assumes it'll hit a hash entry, but it's
>possible... I'll have to get the source and check it out.

Okay, I've checked, and 'ps -l' does no bounds checking for WCHAN, it
appears.  Effectively, this means that if psdatabase is out of sync,
'ps -l' can cause demons to fly out of your nose.  I've sent a patch
off to the maintainer, Charles Blake <cblake@ucsd.edu> to fix the
problem.  Nevertheless, it seems that it should either give bad data
in WCHAN or dump core, with no ill effects outside of that.

http://www.wp.com/joelh --- Joel Ray Holveck --- joelh@gnu.ai.mit.edu

Fourth law of computing:
  Anything that can go wro
.signature: segmentation violation -- core dumped

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