pnp code and irq 2 broken

[Doug Rabson]

On Wed, 2003-08-27 at 06:45, John Hay wrote:
> Hi,
> 
> Somewhere along the line the code in FreeBSD that maps irq 2 to irq 9 has
> gone away and a panic was added if one tries to use irq 2. This is all
> well and fine, except that the pnp code was not notified of this. :-) So
> if you have a pnp device that have irq 2 in its mask and FreeBSD then
> decides that irq 2 is a good irq to use for this device, you have an
> instant panic.
> 
> I have worked around it with this crude patch below. Crude because:
> 1) I don't know if it should be an i386 only fix, and
> 2) I used 0x04 directly, maybe IRQ_SLAVE from i386/isa/icu.h or
> some other define should be used?
> 
> Any comments from anyone?

I think that the way this used to work was that irq 2 was never included
in the irq resource map. The allocation code would never choose a
configuration which used irq 2 because it should never be possible to
allocate that resource.