PCI/AER: Clear only ERR_NONFATAL bits during non-fatal recovery

pci_cleanup_aer_uncorrect_error_status() is called by driver .slot_reset()
methods when handling ERR_NONFATAL errors.  Previously this cleared *all*
the bits, including ERR_FATAL bits.

Since we're only handling ERR_NONFATAL errors, clear only the ERR_NONFATAL
error status bits.

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: split to separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pcie/aer.c

@@ -385,13 +385,16 @@ EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
 int pci_cleanup_aer_uncorrect_error_status(struct pci_dev *dev)
 {
 	int pos;
-	u32 status;
+	u32 status, sev;
 
 	pos = dev->aer_cap;
 	if (!pos)
 		return -EIO;
 
+	/* Clear status bits for ERR_NONFATAL errors only */
 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
+	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &sev);
+	status &= ~sev;
 	if (status)
 		pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);