--- zzzz-none-000/linux-3.10.107/drivers/xen/xen-pciback/pciback_ops.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/xen/xen-pciback/pciback_ops.c	2021-02-04 17:41:59.000000000 +0000
@@ -3,6 +3,9 @@
  *
  *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
  */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/wait.h>
 #include <linux/bitops.h>
@@ -156,7 +159,7 @@
 		status = pci_enable_msi(dev);
 
 	if (status) {
-		pr_warn_ratelimited(DRV_NAME ": %s: error enabling MSI for guest %u: err %d\n",
+		pr_warn_ratelimited("%s: error enabling MSI for guest %u: err %d\n",
 				    pci_name(dev), pdev->xdev->otherend_id,
 				    status);
 		op->value = 0;
@@ -224,8 +227,9 @@
 	/*
 	 * PCI_COMMAND_MEMORY must be enabled, otherwise we may not be able
 	 * to access the BARs where the MSI-X entries reside.
+	 * But VF devices are unique in which the PF needs to be checked.
 	 */
-	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	pci_read_config_word(pci_physfn(dev), PCI_COMMAND, &cmd);
 	if (dev->msi_enabled || !(cmd & PCI_COMMAND_MEMORY))
 		return -ENXIO;
 
@@ -238,12 +242,11 @@
 		entries[i].vector = op->msix_entries[i].vector;
 	}
 
-	result = pci_enable_msix(dev, entries, op->value);
-
+	result = pci_enable_msix_exact(dev, entries, op->value);
 	if (result == 0) {
 		for (i = 0; i < op->value; i++) {
 			op->msix_entries[i].entry = entries[i].entry;
-			if (entries[i].vector)
+			if (entries[i].vector) {
 				op->msix_entries[i].vector =
 					xen_pirq_from_irq(entries[i].vector);
 				if (unlikely(verbose_request))
@@ -251,9 +254,10 @@
 						"MSI-X[%d]: %d\n",
 						pci_name(dev), i,
 						op->msix_entries[i].vector);
+			}
 		}
 	} else
-		pr_warn_ratelimited(DRV_NAME ": %s: error enabling MSI-X for guest %u: err %d!\n",
+		pr_warn_ratelimited("%s: error enabling MSI-X for guest %u: err %d!\n",
 				    pci_name(dev), pdev->xdev->otherend_id,
 				    result);
 	kfree(entries);
@@ -394,9 +398,9 @@
 	notify_remote_via_irq(pdev->evtchn_irq);
 
 	/* Mark that we're done. */
-	smp_mb__before_clear_bit(); /* /after/ clearing PCIF_active */
+	smp_mb__before_atomic(); /* /after/ clearing PCIF_active */
 	clear_bit(_PDEVF_op_active, &pdev->flags);
-	smp_mb__after_clear_bit(); /* /before/ final check for work */
+	smp_mb__after_atomic(); /* /before/ final check for work */
 
 	/* Check to see if the driver domain tried to start another request in
 	 * between clearing _XEN_PCIF_active and clearing _PDEVF_op_active.
@@ -421,7 +425,7 @@
 		dev_data->handled++;
 		if ((dev_data->handled % 1000) == 0) {
 			if (xen_test_irq_shared(irq)) {
-				printk(KERN_INFO "%s IRQ line is not shared "
+				pr_info("%s IRQ line is not shared "
 					"with other domains. Turning ISR off\n",
 					 dev_data->irq_name);
 				dev_data->ack_intr = 0;