PCI/ERR: Retain status from error notification

Overwriting the frozen detected status with the result of the link reset
loses the NEED_RESET result that drivers are depending on for error
handling to report the .slot_reset() callback. Retain this status so
that subsequent error handling has the correct flow.

Link: https://lore.kernel.org/r/20210104230300.1277180-4-kbusch@kernel.orgReported-by: Hinko Kocevar <hinko.kocevar@ess.eu>
Tested-by: Hedi Berriche <hedi.berriche@hpe.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sean V Kelley <sean.v.kelley@intel.com>
Acked-by: Hedi Berriche <hedi.berriche@hpe.com>

drivers/pci/pcie/err.c

@@ -198,8 +198,7 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
 	pci_dbg(bridge, "broadcast error_detected message\n");
 	if (state == pci_channel_io_frozen) {
 		pci_walk_bridge(bridge, report_frozen_detected, &status);
-		status = reset_subordinates(bridge);
-		if (status != PCI_ERS_RESULT_RECOVERED) {
+		if (reset_subordinates(bridge) != PCI_ERS_RESULT_RECOVERED) {
 			pci_warn(bridge, "subordinate device reset failed\n");
 			goto failed;
 		}