Fault Reporting

This following function notifies the system that your driver has discovered a device fault.

void ddi_dev_report_fault(dev_info_t *dip, ddi_fault_impact_t impact,
             ddi_fault_location_t location, const char *message);

The impact parameter indicates the impact of the fault on the device's ability to provide normal service, and is used by the fault management components of the system to determine the appropriate action to take in response to the fault. This action can cause a change in the device state. A service-lost fault causes the device state to be changed to DOWN and a service-degraded fault causes the device state to be changed to DEGRADED.

A device should be reported as faulty if:

• A PIO error is detected.

• Corrupted data is detected.

• The device has locked up.

Drivers should avoid reporting the same fault repeatedly, if possible. In particular, it is redundant (and undesirable) for drivers to report any errors if the device is already in an unusable state (see ddi_get_devstate(9F)).

If a hardware fault is detected during the attach process, the driver must report the fault by using ddi_dev_report_fault(9F) as well as by returning DDI_FAILURE.