Merge tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - EDID interfaces for vfio devices supporting display extensions (Gerd
   Hoffmann)

 - Generically select Type-1 IOMMU model support on ARM/ARM64 (Geert
   Uytterhoeven)

 - Quirk for VFs reporting INTx pin (Alex Williamson)

 - Fix error path memory leak in MSI support (Li Qiang)

* tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio:
  vfio: add edid support to mbochs sample driver
  vfio: add edid api for display (vgpu) devices.
  drivers/vfio: Allow type-1 IOMMU instantiation with all ARM/ARM64 IOMMUs
  vfio/pci: Mask buggy SR-IOV VF INTx support
  vfio/pci: Fix potential memory leak in vfio_msi_cap_len

drivers/vfio/Kconfig

@@ -21,7 +21,7 @@ config VFIO_VIRQFD
 menuconfig VFIO
 	tristate "VFIO Non-Privileged userspace driver framework"
 	depends on IOMMU_API
-	select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM_SMMU || ARM_SMMU_V3)
+	select VFIO_IOMMU_TYPE1 if (X86 || S390 || ARM || ARM64)
 	select ANON_INODES
 	help
 	  VFIO provides a framework for secure userspace device drivers.

drivers/vfio/pci/vfio_pci.c

@@ -434,10 +434,14 @@ static int vfio_pci_get_irq_count(struct vfio_pci_device *vdev, int irq_type)
 {
 	if (irq_type == VFIO_PCI_INTX_IRQ_INDEX) {
 		u8 pin;
+
+		if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) ||
+		    vdev->nointx || vdev->pdev->is_virtfn)
+			return 0;
+
 		pci_read_config_byte(vdev->pdev, PCI_INTERRUPT_PIN, &pin);
-		if (IS_ENABLED(CONFIG_VFIO_PCI_INTX) && !vdev->nointx && pin)
-			return 1;
 
+		return pin ? 1 : 0;
 	} else if (irq_type == VFIO_PCI_MSI_IRQ_INDEX) {
 		u8 pos;
 		u16 flags;

drivers/vfio/pci/vfio_pci_config.c

@@ -1180,8 +1180,10 @@ static int vfio_msi_cap_len(struct vfio_pci_device *vdev, u8 pos)
 		return -ENOMEM;
 
 	ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags);
-	if (ret)
+	if (ret) {
+		kfree(vdev->msi_perm);
 		return ret;
+	}
 
 	return len;
 }
@@ -1609,6 +1611,15 @@ static int vfio_ecap_init(struct vfio_pci_device *vdev)
 	return 0;
 }
 
+/*
+ * Nag about hardware bugs, hopefully to have vendors fix them, but at least
+ * to collect a list of dependencies for the VF INTx pin quirk below.
+ */
+static const struct pci_device_id known_bogus_vf_intx_pin[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x270c) },
+	{}
+};
+
 /*
  * For each device we allocate a pci_config_map that indicates the
  * capability occupying each dword and thus the struct perm_bits we
@@ -1674,6 +1685,24 @@ int vfio_config_init(struct vfio_pci_device *vdev)
 	if (pdev->is_virtfn) {
 		*(__le16 *)&vconfig[PCI_VENDOR_ID] = cpu_to_le16(pdev->vendor);
 		*(__le16 *)&vconfig[PCI_DEVICE_ID] = cpu_to_le16(pdev->device);
+
+		/*
+		 * Per SR-IOV spec rev 1.1, 3.4.1.18 the interrupt pin register
+		 * does not apply to VFs and VFs must implement this register
+		 * as read-only with value zero.  Userspace is not readily able
+		 * to identify whether a device is a VF and thus that the pin
+		 * definition on the device is bogus should it violate this
+		 * requirement.  We already virtualize the pin register for
+		 * other purposes, so we simply need to replace the bogus value
+		 * and consider VFs when we determine INTx IRQ count.
+		 */
+		if (vconfig[PCI_INTERRUPT_PIN] &&
+		    !pci_match_id(known_bogus_vf_intx_pin, pdev))
+			pci_warn(pdev,
+				 "Hardware bug: VF reports bogus INTx pin %d\n",
+				 vconfig[PCI_INTERRUPT_PIN]);
+
+		vconfig[PCI_INTERRUPT_PIN] = 0; /* Gratuitous for good VFs */
 	}
 
 	if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX) || vdev->nointx)

include/uapi/linux/vfio.h

@@ -303,6 +303,56 @@ struct vfio_region_info_cap_type {
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_HOST_CFG	(2)
 #define VFIO_REGION_SUBTYPE_INTEL_IGD_LPC_CFG	(3)
 
+#define VFIO_REGION_TYPE_GFX                    (1)
+#define VFIO_REGION_SUBTYPE_GFX_EDID            (1)
+
+/**
+ * struct vfio_region_gfx_edid - EDID region layout.
+ *
+ * Set display link state and EDID blob.
+ *
+ * The EDID blob has monitor information such as brand, name, serial
+ * number, physical size, supported video modes and more.
+ *
+ * This special region allows userspace (typically qemu) set a virtual
+ * EDID for the virtual monitor, which allows a flexible display
+ * configuration.
+ *
+ * For the edid blob spec look here:
+ *    https://en.wikipedia.org/wiki/Extended_Display_Identification_Data
+ *
+ * On linux systems you can find the EDID blob in sysfs:
+ *    /sys/class/drm/${card}/${connector}/edid
+ *
+ * You can use the edid-decode ulility (comes with xorg-x11-utils) to
+ * decode the EDID blob.
+ *
+ * @edid_offset: location of the edid blob, relative to the
+ *               start of the region (readonly).
+ * @edid_max_size: max size of the edid blob (readonly).
+ * @edid_size: actual edid size (read/write).
+ * @link_state: display link state (read/write).
+ * VFIO_DEVICE_GFX_LINK_STATE_UP: Monitor is turned on.
+ * VFIO_DEVICE_GFX_LINK_STATE_DOWN: Monitor is turned off.
+ * @max_xres: max display width (0 == no limitation, readonly).
+ * @max_yres: max display height (0 == no limitation, readonly).
+ *
+ * EDID update protocol:
+ *   (1) set link-state to down.
+ *   (2) update edid blob and size.
+ *   (3) set link-state to up.
+ */
+struct vfio_region_gfx_edid {
+	__u32 edid_offset;
+	__u32 edid_max_size;
+	__u32 edid_size;
+	__u32 max_xres;
+	__u32 max_yres;
+	__u32 link_state;
+#define VFIO_DEVICE_GFX_LINK_STATE_UP    1
+#define VFIO_DEVICE_GFX_LINK_STATE_DOWN  2
+};
+
 /*
  * The MSIX mappable capability informs that MSIX data of a BAR can be mmapped
  * which allows direct access to non-MSIX registers which happened to be within