Presumably the interrupt that notifies one that a card has been pulled is actually then managed by the bus device driver for that bus. This should ensure that the the bus nexus controlller is notified that the state of the hardware is changed.

This does nothing for threads that were active at the time of the interrupt. In this case, either the hardware is sane enough to continue to provide some rational non-faulting access (in the case of memory mapping), or you have to design a framework such that when the interrupt occurs, and the nexus driver now knows how to remap any memory mappings so that a safe non-faulting (if nonsensical) access can occur. Then some additional mechanism which notifies the actual node driver that things have changed will be invoked.

For systems I'm more familiar with, explicit obligate parent-child relationships have these specific notification mechanisms specified on a per parent-child type basis. It's hard to generalize such mechanisms into a usable general event notification mechanism because each bus has different possible async events. A PC cardbus has removal/insertion, a fibre channel arbitrated loop has LIP and then (re)arbitration for AL_PAs- who knows what Compact PCI provides?

What does newbus provide for this?

-matt

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