panic after kldunload - stale device descriptions

Frank Behrens frank at
Tue Aug 23 19:44:32 GMT 2005

To answer myself:

Frank Behrens <frank at> wrote on 23 Aug 2005 19:43:

> I loaded my driver (kldload) and the device was probed and found in 
> ISA_PNP_PROBE. Then the driver was unloaded (kldunload) and I tried 
> to read the current device configuration. This gave me a
> Fatal trap 12: page fault while in kernel mode

I could not reproduce the error. May be the driver did not release a 
resource, so it was unloaded, but the device was still present.

In that case there is no danger, because we can assume safely all 
driver will release all allocated resources.

Frank Behrens, Osterwieck, Germany
PGP-key 0x5B7C47ED on public servers available.

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