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Date: Wed, 1 Nov 1995 03:48:19 +0800 (WST)
From: Peter Wemm <peter@jhome.DIALix.COM>
To: David Greenman <davidg@Root.COM>
cc: CVS-commiters@freefall.freebsd.org, cvs-sys@freefall.freebsd.org
Subject: Re: cvs commit: src/sys/kern tty_subr.c 
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On Tue, 31 Oct 1995, David Greenman wrote:
> >hsu         95/10/31 11:00:05
( ^^^^ aargh!!! )

> >  Modified:    sys/kern  tty_subr.c
> >  Log:
> >  Make a putc()/b_to_q() to a clist that hasn't had cblocks reserved
> >  non-fatal.  I've make it return an appropriate error to the caller instead
> >  of panic()ing.
> >  
> >  Handling an error condition is inherently more friendly than exploding
> >  the kernel.. :-)  The new behavior is a little closer to traditional
> >  clists, potentially making porting a little simpler.
> >  
> >  Suggested by: bde (many months ago, I've been using this for a while..)
> 
>    It's really strange that you should be committing this now - wcarchive just
> crashed because of this only a few minutes before your commit!
>    (I'm sure you had nothing to do with it...right? :-))

Honest, I swear I never knew..  Oh wow.. Perhaps I should go out and buy 
a lottery ticket or something... :-) :-)  (or keep clear of mirrors/black 
cats etc - I'm not sure if this is a good or bad omen... :-)

I used to have this problem occasionally with the specialix driver, and in
the end the interrupt routine had to do a lot of tests to attempt to
intuit whether or not he cblocks were currently reserved or not.  The
thought occurred to me this morning that the driver that is in -current
has only been seriously stress tested with this modification in the
kernel. 

-Peter

> -DG
>