Merge tag 'vfio-v4.13-rc4' of git://github.com/awilliam/linux-vfio

Pull VFIO fixes from Alex Williamson:

 - SPAPR/EEH config build fix (Murilo Opsfelder Araujo)

 - Fix possible device lock deadlock (Alex Williamson)

 - Correctly size integrated endpoint PCIe capabilities (Alex
   Williamson)

* tag 'vfio-v4.13-rc4' of git://github.com/awilliam/linux-vfio:
  vfio/pci: Fix handling of RC integrated endpoint PCIe capability size
  vfio/pci: Use pci_try_reset_function() on initial open
  include/linux/vfio.h: Guard powerpc-specific functions with CONFIG_VFIO_SPAPR_EEH

Author: torvalds

drivers/vfio/pci/vfio_pci.c

@@ -226,7 +226,14 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
 	if (ret)
 		return ret;
 
-	vdev->reset_works = (pci_reset_function(pdev) == 0);
+	/* If reset fails because of the device lock, fail this path entirely */
+	ret = pci_try_reset_function(pdev);
+	if (ret == -EAGAIN) {
+		pci_disable_device(pdev);
+		return ret;
+	}
+
+	vdev->reset_works = !ret;
 	pci_save_state(pdev);
 	vdev->pci_saved_state = pci_store_saved_state(pdev);
 	if (!vdev->pci_saved_state)

drivers/vfio/pci/vfio_pci_config.c

@@ -839,7 +839,7 @@ static int vfio_exp_config_write(struct vfio_pci_device *vdev, int pos,
 /* Permissions for PCI Express capability */
 static int __init init_pci_cap_exp_perm(struct perm_bits *perm)
 {
-	/* Alloc larger of two possible sizes */
+	/* Alloc largest of possible sizes */
 	if (alloc_perm_bits(perm, PCI_CAP_EXP_ENDPOINT_SIZEOF_V2))
 		return -ENOMEM;
 
@@ -1243,11 +1243,16 @@ static int vfio_cap_len(struct vfio_pci_device *vdev, u8 cap, u8 pos)
 			vdev->extended_caps = (dword != 0);
 		}
 
-		/* length based on version */
-		if ((pcie_caps_reg(pdev) & PCI_EXP_FLAGS_VERS) == 1)
+		/* length based on version and type */
+		if ((pcie_caps_reg(pdev) & PCI_EXP_FLAGS_VERS) == 1) {
+			if (pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END)
+				return 0xc; /* "All Devices" only, no link */
 			return PCI_CAP_EXP_ENDPOINT_SIZEOF_V1;
-		else
+		} else {
+			if (pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END)
+				return 0x2c; /* No link */
 			return PCI_CAP_EXP_ENDPOINT_SIZEOF_V2;
+		}
 	case PCI_CAP_ID_HT:
 		ret = pci_read_config_byte(pdev, pos + 3, &byte);
 		if (ret)

include/linux/vfio.h

@@ -152,7 +152,7 @@ extern int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
 					      size_t *data_size);
 
 struct pci_dev;
-#ifdef CONFIG_EEH
+#if IS_ENABLED(CONFIG_VFIO_SPAPR_EEH)
 extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
 extern void vfio_spapr_pci_eeh_release(struct pci_dev *pdev);
 extern long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
@@ -173,7 +173,7 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
 {
 	return -ENOTTY;
 }
-#endif /* CONFIG_EEH */
+#endif /* CONFIG_VFIO_SPAPR_EEH */
 
 /*
  * IRQfd - generic