Bjorn,
>> diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
>> index ed4d094..7abefd9 100644
>> --- a/drivers/pci/pcie/portdrv_pci.c
>> +++ b/drivers/pci/pcie/portdrv_pci.c
>> @@ -332,13 +332,11 @@ static pci_ers_result_t pcie_portdrv_slot_reset(struct pci_dev *dev)
>> pci_ers_result_t status = PCI_ERS_RESULT_RECOVERED;
>> int retval;
>>
>> - /* If fatal, restore cfg space for possible link reset at upstream */
>> - if (dev->error_state == pci_channel_io_frozen) {
>> - dev->state_saved = true;
>> - pci_restore_state(dev);
>> - pcie_portdrv_restore_config(dev);
>> - pci_enable_pcie_error_reporting(dev);
>> - }
>> + /* restore cfg space for possible link reset at upstream */
>> + dev->state_saved = true;
>> + pci_restore_state(dev);
>> + pcie_portdrv_restore_config(dev);
>> + pci_enable_pcie_error_reporting(dev);
>>
>> /* get true return value from &status */
>> retval = device_for_each_child(&dev->dev, &status, slot_reset_iter);
>
>I think this patch changes the behavior in the case of a non-fatal error
>where one of the .error_detected() methods returned
>PCI_ERS_RESULT_NEED_RESET. In that case, pcie_portdrv_slot_reset()
>previously did not restore config space, but after your patch, it *will*
>restore it. We need an explanation of why this is safe.
Here is my understanding of this part of the patch:
I think your concern here should not be an issue. Whether it is a non-fatal error or a fatal error, as long as one of the .error_detected() method from the downstream drivers involved returns a PCI_ERS_RESULT_NEED_RESET, it should trump all others and a slot reset should be performed, even though it was originally due to a non-fatal error reported or only one of the downstream drivers requests it. In the case of AER driver, this should be implemented in the broadcast_error_message() with pci_walk_bus() by passing in the report_error_detected() function, and merging the results into the result_data->result...
In any case, the fact that this pcie_portdrv_slot_reset() being invoked should be considered as a aftermath of a slot reset has been performed, thus the restore of config space should be performed after the reset. I suppose the restore should be to the same state as fresh power-on states, right?
Thanks,
Joe Liu, Ph.D.
Senior Principal Engineer
Emulex Corporation
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