>Number:         3355
>Category:       kern
>Synopsis:       if_de causes panic on media change
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Mar 18 13:05:01 1997
>Last-Modified:
>Originator:     Matthias Scheler
>Organization:
Matthias Scheler                                http://home.pages.de/~tron/
>Release:        970317
>Environment:
System: NetBSD lyssa 1.2D NetBSD 1.2D (LYSSA) #4: Tue Mar 18 21:15:25 MET 1997 tron@lyssa:/usr/src/sys/arch/i386/compile/LYSSA i386


>Description:
Hoping for a fix for kern/3141 I installed a kernel with media support today.
After the reboot I checked the media type:

tron@lyssa:~>ifconfig de0
de0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST>
        media: autoselect status: no carrier
        inet 194.121.202.186 netmask 0xfffffff8 broadcast 194.121.202.191

Although the driver had a different opinion about that the network worked
fine via the AUI/BNC port. Now I tried to change it to BNC manually
with "ifconfig de0 media bnc" and got a panic:

reboot after panic: tulip_media_poll: botch at 769

I checked the sources and found out that the panic is caused by this
"switch" statement in "tulip_media_poll":

        switch (sc->tulip_probe_state) {
...
            default: {
#if defined(DIAGNOSTIC)
                panic("tulip_media_poll: botch at line %d\n", __LINE__);
#endif
                break;
            }    

I tried to modify the kernel to print the contents of "sc->tulip_probe_state"
but the damned bug doesn't occur with such a modified kernel. :-(

>How-To-Repeat:
ifconfig de0
ifconfig de0 media bnc

>Fix:
Sorry, I don't even know how to trace it.
>Audit-Trail:
>Unformatted: