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Date: Tue, 16 Sep 2003 12:25:31 -0700 (PDT)
From: Nate Lawson <nate@root.org>
To: Andrew Thompson <andy@fud.org.nz>
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Subject: Re: ACPI and a Toshiba Tecra 8000
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On Wed, 17 Sep 2003, Andrew Thompson wrote:
> Nate Lawson wrote:
> >    gdb kernel.debug
> >    l *scsuspend+0x17
> >That should show the offending code segment.
>
> (gdb) l *scsuspend+0x17
> 0xc03d7b17 is in scsuspend (/usr/src/sys/isa/syscons_isa.c:111).
> 106             int             retry = 10;
> 107             static int      dummy;
> 108             sc_softc_t      *sc;
> 109
> 110             sc = &main_softc;
> 111             sc_cur_scr = sc->cur_scp->index;
> 112
> 113             if (sc_no_suspend_vtswitch)
> 114                     return (0);
> 115

Ok, this shows it's not ok to unconditionally deref sc->cur_scp.  Now I'll
look for what cases it is NULL.  I'll get back to you in a day or so.

-Nate