Merge branch 'pci/msi'

  - Avoid panic when drivers enable MSI/MSI-X twice (Tonghao Zhang)

* pci/msi:
  PCI/MSI: Warn and return error if driver enables MSI/MSI-X twice

drivers/pci/msi.c

@@ -958,7 +958,6 @@ static int __pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries,
 			}
 		}
 	}
-	WARN_ON(!!dev->msix_enabled);
 
 	/* Check whether driver already requested for MSI irq */
 	if (dev->msi_enabled) {
@@ -1028,8 +1027,6 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
 	if (!pci_msi_supported(dev, minvec))
 		return -EINVAL;
 
-	WARN_ON(!!dev->msi_enabled);
-
 	/* Check whether driver already requested MSI-X irqs */
 	if (dev->msix_enabled) {
 		pci_info(dev, "can't enable MSI (MSI-X already enabled)\n");
@@ -1039,6 +1036,9 @@ static int __pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec,
 	if (maxvec < minvec)
 		return -ERANGE;
 
+	if (WARN_ON_ONCE(dev->msi_enabled))
+		return -EINVAL;
+
 	nvec = pci_msi_vec_count(dev);
 	if (nvec < 0)
 		return nvec;
@@ -1087,6 +1087,9 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
 	if (maxvec < minvec)
 		return -ERANGE;
 
+	if (WARN_ON_ONCE(dev->msix_enabled))
+		return -EINVAL;
+
 	for (;;) {
 		if (affd) {
 			nvec = irq_calc_affinity_vectors(minvec, nvec, affd);