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Re: psdatabase file in /boot



Joel Ray Holveck writes:
 > 
 > >>> 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.
 > 
 > -- 

    Evidedly nod.

    Thages.



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