Fatal trap 30: reserved (unknown) fault

[Christoph Mallon]

Alexander Motin schrieb:
> Hi.
> 
> About month ago after one of my amd64 8-CURRENT upgrade I have started 
> to see crashes with very strange message:
> Fatal trap 30: reserved (unknown) fault while in kernel mode
> 
> Crash usually happens during some driver loading or unloading, for 
> example, snd_hda, which always worked fine before, or during ata channel 
> detach/attach which also causes device destruction/creation. Backtrace 
> of this state shows nothing interesting, for example idling in 
> acpi_cpu_c1() or just DELAY().
> 
> Does anybody knows, for whom is this fault "reserved" and what does it 
> mean?

Intel:
   20-31 -- Intel reserved. Do not use.

This exception really should not happen. Maybe int 0x30 is executed, but 
this should not be the case either.