[ On Saturday, November 9, 2002 at 09:59:13 (+0200), Alan Barrett wrote: ]
> Subject: Re: killing the unkillable
>
> On Fri, 08 Nov 2002, Julio Merino wrote:
> > "Jeremy C. Reed" <reed@reedmedia.net> wrote:
> > > Can someone point me to the code or documentation about why some
> > > processes won't be killed?
> > I do not know, but this is *very* *annoying*.
> 
> It sometimes helps to call revoke(2) on a pathname that refers to the
> device that is wedged.
> 
> Perhaps we need a new syscall to *really* kill a process, even if it's
> in a state where normal signal delivery does not happen.  Late 1980's
> Apollo Domain-OS had a "kill -lbolt" command that sent a "lightning
> bolt" that worked even where "kill -9" did not work.

Perhaps we should just fix SIGKILL so that it does what it's supposed to
do.  There should be no need to have a SIGREALLYKILLITDEAD when that's
what SIGKILL is really already supposed to be.  SIGLBOLT was a very bad
hack piled on top of a broken implementation.  (and of course literally
wasn't SIGLBOLT just a way to invoke wakeup(lbolt)?)

This is in some ways related to the same kinds of problems that can
happen with processes that hang in _exit() (i.e. before they become
zombies) waiting for events that never (and sometimes cannot ever)
happen.  This issue was discussed briefly on this list back in late
Oct. of 2000.

-- 
								Greg A. Woods

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