hardware configuration

My device uses 2 IO ports and 1 interrupt. It’s PnP device. So it
must query PnP Manager for resources. PnP Manager as I know send then
IRP_MN_FILTER_RESOURCE_REQUIREMENTS Irp, where
Irp->IoStatus.Information is pointer to IO_RESOURCE_REQUIREMENTS_LIST
structure. My driver receives thas Irp, but IoStatus.Information is 0.
How can it be? But resources normally allocated for driver! It’s need
to say, that IRQ and one IO range works fine, but second IO range is
bad - all read requests return 0xfeff. And native vendor drivers also
works fine. Could you explain that?
Thanks.

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