s390/pci: Do not try re-enabling load/store if device is disabled

If a device is disabled unblocking load/store on its own is not useful
as a full re-enable of the function is necessary anyway. Note that SCLP
Write Event Data Action Qualifier 0 (Reset) leaves the device disabled
and triggers this case unless the driver already requests a reset.

Cc: [email protected]
Fixes: 4cdf2f4 ("s390/pci: implement minimal PCI error recovery")
Reviewed-by: Farhan Ali <[email protected]>
Signed-off-by: Niklas Schnelle <[email protected]>
Signed-off-by: Alexander Gordeev <[email protected]>

Author: niklas88

arch/s390/pci/pci_event.c

@@ -106,6 +106,10 @@ static pci_ers_result_t zpci_event_do_error_state_clear(struct pci_dev *pdev,
 	struct zpci_dev *zdev = to_zpci(pdev);
 	int rc;
 
+	/* The underlying device may have been disabled by the event */
+	if (!zdev_enabled(zdev))
+		return PCI_ERS_RESULT_NEED_RESET;
+
 	pr_info("%s: Unblocking device access for examination\n", pci_name(pdev));
 	rc = zpci_reset_load_store_blocked(zdev);
 	if (rc) {