Panic in 7.1-PRERELEASE (was: Re: kgdb on sparc64)

[Marius Strobl]

On Wed, Nov 19, 2008 at 09:03:44AM +0100, Ruben de Groot wrote:
> 
> FreeBSD nostalgia4infinity.bzerk.org 7.1-PRERELEASE FreeBSD 7.1-PRERELEASE #5: Mon Nov 10 21:25:55 CET 2008     root at nostalgia4infinity.bzerk.org:/usr/obj/usr/src/sys/N4I  sparc64
> 
> panic: trap: data access error
> cpuid = 0
> KDB: stack backtrace:
> panic() at panic+0x1c8
> trap() at trap+0x4d0
> -- data access error %o7=0xc00bac60 --
> dc_mii_writebit() at dc_mii_writebit+0xd8
> dc_miibus_writereg() at dc_miibus_writereg+0x2a0
> miibus_writereg() at miibus_writereg+0x64
> mii_phy_reset() at mii_phy_reset+0x7c
> mii_phy_tick() at mii_phy_tick+0x154
> amphy_service() at amphy_service+0x164
> mii_tick() at mii_tick+0x1c
> dc_tick() at dc_tick+0x1ec
> softclock() at softclock+0x3c4
> ithread_loop() at ithread_loop+0x21c
> fork_exit() at fork_exit+0x88
> fork_trampoline() at fork_trampoline+0x8
> Uptime: 4d22h16m5s
> Dumping 1024 MB (4 chunks)
>   chunk at 0: 268435456 bytes ... ok
>   chunk at 0x20000000: 268435456 bytes ... ok
>   chunk at 0x40000000: 268435456 bytes ... ok
>   chunk at 0x60000000: 268435456 bytes ... ok
> 

Could you please run gdb on the corresponding kernel.debug
and report the output of the following commands?
l*(0xc00bac60)
l*(dc_mii_writebit+0xd8)

If you need a quick workaround I think that locally reverting
src/sys/dev/dc/if_dc.c r182461/1.192.2.5 will get you rid of
this problem, this will also make dc(4) again no longer check
the link state of this interface once it's up though, so this
is no real solution.

Marius