Re: port-amd64/39630: New ipmi(4) attachment code triggers kernel panic

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

Matthias Scheler wrote:
>       Hello,
> 
> I've added the following debugging output:
> 
> Index: ipmi.c
> ===================================================================
> RCS file: /cvsroot/src/sys/arch/x86/x86/ipmi.c,v
> retrieving revision 1.21
> diff -u -r1.21 ipmi.c
> --- ipmi.c    30 Oct 2008 20:28:02 -0000      1.21
> +++ ipmi.c    4 Nov 2008 17:53:45 -0000
> @@ -292,19 +292,23 @@
>       struct ipmi_softc       *sc = arg;
>       struct ipmi_bmc_args    *a = sc->sc_iowait_args;
>  
> +     aprint_normal("_bmc_io_wait: sc=%p, a=%p\n", sc, a);
>       *a->v = bmc_read(sc, a->offset);
>       if ((*a->v & a->mask) == a->value) {
> +             aprint_normal("_bmc_io_wait: wakeup success\n");
>               sc->sc_wakeup = 0;
>               wakeup(sc);
>               return;
>       }
>  
>       if (++sc->sc_retries > sc->sc_max_retries) {
> +             aprint_normal("_bmc_io_wait: wakeup failure\n");
>               sc->sc_wakeup = 0;
>               wakeup(sc);
>               return;
>       }
>  
> +     aprint_normal("_bmc_io_wait: callout\n");
>       callout_schedule(&sc->sc_callout, 1);
>  }
>  
> @@ -1756,6 +1760,7 @@
>       sc->sc_max_retries = hz / 2; /* 0.5 seconds max */
>       callout_init(&sc->sc_callout, 0);
>       callout_setfunc(&sc->sc_callout, _bmc_io_wait, sc);
> +     aprint_normal("Callout initialized at %p\n", &sc->sc_callout);
>  
>       /* Map registers */
>       ipmi_map_regs(sc, ia);
> 
> And I get this output:
> 
> attimer0: attached to pcppi0
> _bmc_io_wait: sc=0xffffffff807dea30, a=0xffffffff807de900
> _bmc_io_wait: callout
> uvm_fault(0xffffffff806e7ae0, 0x0, 1) -> e
> fatal page fault in supervisor mode
> 
> It looks to me like _bmc_io_wait() is called before "sc->sc_callout"
> has been initialized.

This has been fixed by christos:
http://mail-index.netbsd.org/source-changes/2008/11/03/msg212193.html

Christoph