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[[!meta title="I've just gotten a db> prompt"]]

Something bad happened in the kernel (think of it as the equivalent of the Linux
Oops). The `db>` prompt is actually the kernel debugger. You can then type the
`trace` command, which will bring you something like:

    0x8007cf1(8088488,5e,40000008,2aa008,0)
    0x80071bc(0,0,0,0,0)
    0x8006831(24fe00,2000,b,800,0)

Which is actually the function call trace, which can be decyphered by using:

    $ addr2line -i -f -e /boot/gnumach 0x8007cf1 0x80071bc 0x8006831

You can then send us the result of the `trace` and the `addr2line`, as well as
the exact version of the gnumach kernel you were running, for further
investigation. [[More information about the gnumach
debugger|microkernel/mach/gnumach/debugging]] is available.