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X-Mailer: exmh version 2.0beta 12/23/96
To: Charlie Root <root@dsu.dp.ua>
cc: bugs@freebsd.org
Subject: Re: err in if_sl.c 
In-reply-to: Your message of "Mon, 06 Jan 1997 13:54:48 +0200."
             <199701061154.NAA00419@dsu.dp.ua> 
Date: Mon, 06 Jan 1997 21:59:12 +0800
From: Peter Wemm <peter@spinner.DIALix.COM>
Sender: owner-bugs@freebsd.org
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Charlie Root wrote:
> 344c344
> # if_sl.c:
> < 		sc->sc_flags &= ~SC_STATIC;
> ---
> # if_sl.c.old
> > 		sc->sc_flags &= SC_STATIC;

Are you sure it's not the intention to clear everything but preserve the 
SC_STATIC bit?

The code in question is:
        if (sc != NULL) {
                if (sc->sc_outfill) {
                        sc->sc_outfill = 0;
                        untimeout(sl_outfill, sc);
                }
                if (sc->sc_keepalive) {
                        sc->sc_keepalive = 0;
                        untimeout(sl_keepalive, sc);
                }                  
                if_down(&sc->sc_if);
                sc->sc_flags &= SC_STATIC;
                sc->sc_ttyp = NULL;
                tp->t_sc = NULL;
                MCLFREE((caddr_t)(sc->sc_ep - SLBUFSIZE));
                sc->sc_ep = 0;
                sc->sc_mp = 0;
                sc->sc_buf = 0;
        }               

This seems to be part of the system that keeps static and dynamic 
allocation apart...

In rev 1.40, there was a change here:

-               sc->sc_flags = 0;
+               sc->sc_flags &= SC_STATIC;

And the log message was:
revision 1.40
date: 1996/05/13 14:09:34;  author: ache;  state: Exp;  lines: +21 -6
Prevent mixing of static and dynamic unit allocation strategies

Cheers,
-Peter