Merge tag 'vfio-v6.18-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Use fdinfo to expose the sysfs path of a device represented by a vfio
   device file (Alex Mastro)

 - Mark vfio-fsl-mc, vfio-amba, and the reset functions for
   vfio-platform for removal as these are either orphaned or believed to
   be unused (Alex Williamson)

 - Add reviewers for vfio-platform to save it from also being marked for
   removal (Mostafa Saleh, Pranjal Shrivastava)

 - VFIO selftests, including basic sanity testing and minimal userspace
   drivers for testing against real hardware. This is also expected to
   provide integration with KVM selftests for KVM-VFIO interfaces (David
   Matlack, Josh Hilke)

 - Fix drivers/cdx and vfio/cdx to build without CONFIG_GENERIC_MSI_IRQ
   (Nipun Gupta)

 - Fix reference leak in hisi_acc (Miaoqian Lin)

 - Use consistent return for unsupported device feature (Alex Mastro)

 - Unwind using the correct memory free callback in vfio/pds (Zilin
   Guan)

 - Use IRQ_DISABLE_LAZY flag to improve handling of pre-PCI2.3 INTx and
   resolve stalled interrupt on ppc64 (Timothy Pearson)

 - Enable GB300 in nvgrace-gpu vfio-pci variant driver (Tushar Dave)

 - Misc:
    - Drop unnecessary ternary conversion in vfio/pci (Xichao Zhao)
    - Grammatical fix in nvgrace-gpu (Morduan Zang)
    - Update Shameer's email address (Shameer Kolothum)
    - Fix document build warning (Alex Williamson)

* tag 'vfio-v6.18-rc1' of https://github.com/awilliam/linux-vfio: (48 commits)
  vfio/nvgrace-gpu: Add GB300 SKU to the devid table
  vfio/pci: Fix INTx handling on legacy non-PCI 2.3 devices
  vfio/pds: replace bitmap_free with vfree
  vfio: return -ENOTTY for unsupported device feature
  hisi_acc_vfio_pci: Fix reference leak in hisi_acc_vfio_debug_init
  vfio/platform: Mark reset drivers for removal
  vfio/amba: Mark for removal
  MAINTAINERS: Add myself as VFIO-platform reviewer
  MAINTAINERS: Add myself as VFIO-platform reviewer
  docs: proc.rst: Fix VFIO Device title formatting
  vfio: selftests: Fix .gitignore for already tracked files
  vfio/cdx: update driver to build without CONFIG_GENERIC_MSI_IRQ
  cdx: don't select CONFIG_GENERIC_MSI_IRQ
  MAINTAINERS: Update Shameer Kolothum's email address
  vfio: selftests: Add a script to help with running VFIO selftests
  vfio: selftests: Make iommufd the default iommu_mode
  vfio: selftests: Add iommufd mode
  vfio: selftests: Add iommufd_compat_type1{,v2} modes
  vfio: selftests: Add vfio_type1v2_mode
  vfio: selftests: Replicate tests across all iommu_modes
  ...

22 files changed, 88 insertions, 19 deletions

diff --git a/drivers/cdx/Kconfig b/drivers/cdx/Kconfig
index 3af41f51cf38..1f1e360507d7 100644
--- a/drivers/cdx/Kconfig
+++ b/drivers/cdx/Kconfig
@@ -8,7 +8,6 @@
 config CDX_BUS
 	bool "CDX Bus driver"
 	depends on OF && ARM64 || COMPILE_TEST
-	select GENERIC_MSI_IRQ
 	help
 	  Driver to enable Composable DMA Transfer(CDX) Bus. CDX bus
 	  exposes Fabric devices which uses composable DMA IP to the
diff --git a/drivers/cdx/cdx.c b/drivers/cdx/cdx.c
index 092306ca2541..3d50f8cd9c0b 100644
--- a/drivers/cdx/cdx.c
+++ b/drivers/cdx/cdx.c
@@ -310,7 +310,7 @@ static int cdx_probe(struct device *dev)
 	 * Setup MSI device data so that generic MSI alloc/free can
 	 * be used by the device driver.
 	 */
-	if (cdx->msi_domain) {
+	if (IS_ENABLED(CONFIG_GENERIC_MSI_IRQ) && cdx->msi_domain) {
 		error = msi_setup_device_data(&cdx_dev->dev);
 		if (error)
 			return error;
@@ -833,7 +833,7 @@ int cdx_device_add(struct cdx_dev_params *dev_params)
 		     ((cdx->id << CDX_CONTROLLER_ID_SHIFT) | (cdx_dev->bus_num & CDX_BUS_NUM_MASK)),
 		     cdx_dev->dev_num);
 
-	if (cdx->msi_domain) {
+	if (IS_ENABLED(CONFIG_GENERIC_MSI_IRQ) && cdx->msi_domain) {
 		cdx_dev->num_msi = dev_params->num_msi;
 		dev_set_msi_domain(&cdx_dev->dev, cdx->msi_domain);
 	}
diff --git a/drivers/cdx/controller/Kconfig b/drivers/cdx/controller/Kconfig
index 0641a4c21e66..a480b62cbd1f 100644
--- a/drivers/cdx/controller/Kconfig
+++ b/drivers/cdx/controller/Kconfig
@@ -10,7 +10,6 @@ if CDX_BUS
 config CDX_CONTROLLER
 	tristate "CDX bus controller"
 	depends on HAS_DMA
-	select GENERIC_MSI_IRQ
 	select REMOTEPROC
 	select RPMSG
 	help
diff --git a/drivers/cdx/controller/cdx_controller.c b/drivers/cdx/controller/cdx_controller.c
index 3f8b9041babf..280f207735da 100644
--- a/drivers/cdx/controller/cdx_controller.c
+++ b/drivers/cdx/controller/cdx_controller.c
@@ -193,7 +193,8 @@ static int xlnx_cdx_probe(struct platform_device *pdev)
 	cdx->ops = &cdx_ops;
 
 	/* Create MSI domain */
-	cdx->msi_domain = cdx_msi_domain_init(&pdev->dev);
+	if (IS_ENABLED(CONFIG_GENERIC_MSI_IRQ))
+		cdx->msi_domain = cdx_msi_domain_init(&pdev->dev);
 	if (!cdx->msi_domain) {
 		ret = dev_err_probe(&pdev->dev, -ENODEV, "cdx_msi_domain_init() failed");
 		goto cdx_msi_fail;
diff --git a/drivers/dma/idxd/registers.h b/drivers/dma/idxd/registers.h
index 9c1c546fe443..02bab136385e 100644
--- a/drivers/dma/idxd/registers.h
+++ b/drivers/dma/idxd/registers.h
@@ -3,7 +3,11 @@
 #ifndef _IDXD_REGISTERS_H_
 #define _IDXD_REGISTERS_H_
 
+#ifdef __KERNEL__
 #include <uapi/linux/idxd.h>
+#else
+#include <linux/idxd.h>
+#endif
 
 /* PCI Config */
 #define PCI_DEVICE_ID_INTEL_DSA_GNRD	0x11fb
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index a180171087a8..12a4a4860a74 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -19,6 +19,8 @@
 
 #define IOAT_DMA_DCA_ANY_CPU		~0
 
+int system_has_dca_enabled(struct pci_dev *pdev);
+
 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, dma_dev)
 #define to_dev(ioat_chan) (&(ioat_chan)->ioat_dma->pdev->dev)
 #define to_pdev(ioat_chan) ((ioat_chan)->ioat_dma->pdev)
diff --git a/drivers/dma/ioat/hw.h b/drivers/dma/ioat/hw.h
index 79e4e4c09c18..0373c48520c9 100644
--- a/drivers/dma/ioat/hw.h
+++ b/drivers/dma/ioat/hw.h
@@ -63,9 +63,6 @@
 #define IOAT_VER_3_3            0x33    /* Version 3.3 */
 #define IOAT_VER_3_4		0x34	/* Version 3.4 */
 
-
-int system_has_dca_enabled(struct pci_dev *pdev);
-
 #define IOAT_DESC_SZ	64
 
 struct ioat_dma_descriptor {
diff --git a/drivers/vfio/cdx/Makefile b/drivers/vfio/cdx/Makefile
index df92b320122a..dadbef2419ea 100644
--- a/drivers/vfio/cdx/Makefile
+++ b/drivers/vfio/cdx/Makefile
@@ -5,4 +5,8 @@
 
 obj-$(CONFIG_VFIO_CDX) += vfio-cdx.o
 
-vfio-cdx-objs := main.o intr.o
+vfio-cdx-objs := main.o
+
+ifdef CONFIG_GENERIC_MSI_IRQ
+vfio-cdx-objs += intr.o
+endif
diff --git a/drivers/vfio/cdx/private.h b/drivers/vfio/cdx/private.h
index dc56729b3114..172e48caa3a0 100644
--- a/drivers/vfio/cdx/private.h
+++ b/drivers/vfio/cdx/private.h
@@ -38,11 +38,25 @@ struct vfio_cdx_device {
 	u8			config_msi;
 };
 
+#ifdef CONFIG_GENERIC_MSI_IRQ
 int vfio_cdx_set_irqs_ioctl(struct vfio_cdx_device *vdev,
 			    u32 flags, unsigned int index,
 			    unsigned int start, unsigned int count,
 			    void *data);
 
 void vfio_cdx_irqs_cleanup(struct vfio_cdx_device *vdev);
+#else
+static int vfio_cdx_set_irqs_ioctl(struct vfio_cdx_device *vdev,
+				   u32 flags, unsigned int index,
+				   unsigned int start, unsigned int count,
+				   void *data)
+{
+	return -EINVAL;
+}
+
+static void vfio_cdx_irqs_cleanup(struct vfio_cdx_device *vdev)
+{
+}
+#endif
 
 #endif /* VFIO_CDX_PRIVATE_H */
diff --git a/drivers/vfio/fsl-mc/Kconfig b/drivers/vfio/fsl-mc/Kconfig
index 7d1d690348f0..43c145d17971 100644
--- a/drivers/vfio/fsl-mc/Kconfig
+++ b/drivers/vfio/fsl-mc/Kconfig
@@ -2,9 +2,12 @@ menu "VFIO support for FSL_MC bus devices"
 	depends on FSL_MC_BUS
 
 config VFIO_FSL_MC
-	tristate "VFIO support for QorIQ DPAA2 fsl-mc bus devices"
+	tristate "VFIO support for QorIQ DPAA2 fsl-mc bus devices (DEPRECATED)"
 	select EVENTFD
 	help
+	  The vfio-fsl-mc driver is deprecated and will be removed in a
+	  future kernel release.
+
 	  Driver to enable support for the VFIO QorIQ DPAA2 fsl-mc
 	  (Management Complex) devices. This is required to passthrough
 	  fsl-mc bus devices using the VFIO framework.
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index f65d91c01f2e..76ccbab0e3d6 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -537,6 +537,8 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 	struct device *dev = &mc_dev->dev;
 	int ret;
 
+	dev_err_once(dev, "DEPRECATION: vfio-fsl-mc is deprecated and will be removed in a future kernel release\n");
+
 	vdev = vfio_alloc_device(vfio_fsl_mc_device, vdev, dev,
 				 &vfio_fsl_mc_ops);
 	if (IS_ERR(vdev))
diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index 397f5e445136..fde33f54e99e 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -1612,8 +1612,10 @@ static void hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vd
 	}
 
 	migf = kzalloc(sizeof(*migf), GFP_KERNEL);
-	if (!migf)
+	if (!migf) {
+		dput(vfio_dev_migration);
 		return;
+	}
 	hisi_acc_vdev->debug_migf = migf;
 
 	vfio_hisi_acc = debugfs_create_dir("hisi_acc", vfio_dev_migration);
@@ -1623,6 +1625,8 @@ static void hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vd
 				    hisi_acc_vf_migf_read);
 	debugfs_create_devm_seqfile(dev, "cmd_state", vfio_hisi_acc,
 				    hisi_acc_vf_debug_cmd);
+
+	dput(vfio_dev_migration);
 }
 
 static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
diff --git a/drivers/vfio/pci/nvgrace-gpu/main.c b/drivers/vfio/pci/nvgrace-gpu/main.c
index d95761dcdd58..e346392b72f6 100644
--- a/drivers/vfio/pci/nvgrace-gpu/main.c
+++ b/drivers/vfio/pci/nvgrace-gpu/main.c
@@ -260,7 +260,7 @@ nvgrace_gpu_ioctl_get_region_info(struct vfio_device *core_vdev,
 	info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index);
 	/*
 	 * The region memory size may not be power-of-2 aligned.
-	 * Given that the memory  as a BAR and may not be
+	 * Given that the memory is a BAR and may not be
 	 * aligned, roundup to the next power-of-2.
 	 */
 	info.size = memregion->bar_size;
@@ -995,6 +995,8 @@ static const struct pci_device_id nvgrace_gpu_vfio_pci_table[] = {
 	{ PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_NVIDIA, 0x2348) },
 	/* GB200 SKU */
 	{ PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_NVIDIA, 0x2941) },
+	/* GB300 SKU */
+	{ PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_NVIDIA, 0x31C2) },
 	{}
 };
 
diff --git a/drivers/vfio/pci/pds/dirty.c b/drivers/vfio/pci/pds/dirty.c
index c51f5e4c3dd6..481992142f79 100644
--- a/drivers/vfio/pci/pds/dirty.c
+++ b/drivers/vfio/pci/pds/dirty.c
@@ -82,7 +82,7 @@ static int pds_vfio_dirty_alloc_bitmaps(struct pds_vfio_region *region,
 
 	host_ack_bmp = vzalloc(bytes);
 	if (!host_ack_bmp) {
-		bitmap_free(host_seq_bmp);
+		vfree(host_seq_bmp);
 		return -ENOMEM;
 	}
 
diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index 123298a4dc8f..30d3e921cb0d 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -304,9 +304,14 @@ static int vfio_intx_enable(struct vfio_pci_core_device *vdev,
 
 	vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
 
+	if (!vdev->pci_2_3)
+		irq_set_status_flags(pdev->irq, IRQ_DISABLE_UNLAZY);
+
 	ret = request_irq(pdev->irq, vfio_intx_handler,
 			  irqflags, ctx->name, ctx);
 	if (ret) {
+		if (!vdev->pci_2_3)
+			irq_clear_status_flags(pdev->irq, IRQ_DISABLE_UNLAZY);
 		vdev->irq_type = VFIO_PCI_NUM_IRQS;
 		kfree(name);
 		vfio_irq_ctx_free(vdev, ctx, 0);
@@ -352,6 +357,8 @@ static void vfio_intx_disable(struct vfio_pci_core_device *vdev)
 		vfio_virqfd_disable(&ctx->unmask);
 		vfio_virqfd_disable(&ctx->mask);
 		free_irq(pdev->irq, ctx);
+		if (!vdev->pci_2_3)
+			irq_clear_status_flags(pdev->irq, IRQ_DISABLE_UNLAZY);
 		if (ctx->trigger)
 			eventfd_ctx_put(ctx->trigger);
 		kfree(ctx->name);
@@ -677,7 +684,7 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_core_device *vdev,
 {
 	struct vfio_pci_irq_ctx *ctx;
 	unsigned int i;
-	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
+	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX);
 
 	if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
 		vfio_msi_disable(vdev, msix);
diff --git a/drivers/vfio/platform/Kconfig b/drivers/vfio/platform/Kconfig
index 88fcde51f024..c6be29b2c24b 100644
--- a/drivers/vfio/platform/Kconfig
+++ b/drivers/vfio/platform/Kconfig
@@ -17,10 +17,13 @@ config VFIO_PLATFORM
 	  If you don't know what to do here, say N.
 
 config VFIO_AMBA
-	tristate "VFIO support for AMBA devices"
+	tristate "VFIO support for AMBA devices (DEPRECATED)"
 	depends on ARM_AMBA || COMPILE_TEST
 	select VFIO_PLATFORM_BASE
 	help
+	  The vfio-amba driver is deprecated and will be removed in a
+	  future kernel release.
+
 	  Support for ARM AMBA devices with VFIO. This is required to make
 	  use of ARM AMBA devices present on the system using the VFIO
 	  framework.
diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig
index dcc08dc145a5..70af0dbe293b 100644
--- a/drivers/vfio/platform/reset/Kconfig
+++ b/drivers/vfio/platform/reset/Kconfig
@@ -1,21 +1,21 @@
 # SPDX-License-Identifier: GPL-2.0-only
 if VFIO_PLATFORM
 config VFIO_PLATFORM_CALXEDAXGMAC_RESET
-	tristate "VFIO support for calxeda xgmac reset"
+	tristate "VFIO support for calxeda xgmac reset (DEPRECATED)"
 	help
 	  Enables the VFIO platform driver to handle reset for Calxeda xgmac
 
 	  If you don't know what to do here, say N.
 
 config VFIO_PLATFORM_AMDXGBE_RESET
-	tristate "VFIO support for AMD XGBE reset"
+	tristate "VFIO support for AMD XGBE reset (DEPRECATED)"
 	help
 	  Enables the VFIO platform driver to handle reset for AMD XGBE
 
 	  If you don't know what to do here, say N.
 
 config VFIO_PLATFORM_BCMFLEXRM_RESET
-	tristate "VFIO support for Broadcom FlexRM reset"
+	tristate "VFIO support for Broadcom FlexRM reset (DEPRECATED)"
 	depends on ARCH_BCM_IPROC || COMPILE_TEST
 	default ARCH_BCM_IPROC
 	help
diff --git a/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c b/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
index abdca900802d..45f386a042a9 100644
--- a/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
+++ b/drivers/vfio/platform/reset/vfio_platform_amdxgbe.c
@@ -52,6 +52,8 @@ static int vfio_platform_amdxgbe_reset(struct vfio_platform_device *vdev)
 	u32 dma_mr_value, pcs_value, value;
 	unsigned int count;
 
+	dev_err_once(vdev->device, "DEPRECATION: VFIO AMD XGBE platform reset is deprecated and will be removed in a future kernel release\n");
+
 	if (!xgmac_regs->ioaddr) {
 		xgmac_regs->ioaddr =
 			ioremap(xgmac_regs->addr, xgmac_regs->size);
diff --git a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
index 1131ebe4837d..51c9d156f307 100644
--- a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
+++ b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
@@ -72,6 +72,8 @@ static int vfio_platform_bcmflexrm_reset(struct vfio_platform_device *vdev)
 	int rc = 0, ret = 0, ring_num = 0;
 	struct vfio_platform_region *reg = &vdev->regions[0];
 
+	dev_err_once(vdev->device, "DEPRECATION: VFIO Broadcom FlexRM platform reset is deprecated and will be removed in a future kernel release\n");
+
 	/* Map FlexRM ring registers if not mapped */
 	if (!reg->ioaddr) {
 		reg->ioaddr = ioremap(reg->addr, reg->size);
diff --git a/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
index 63cc7f0b2e4a..a298045a8e19 100644
--- a/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
+++ b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
@@ -50,6 +50,8 @@ static int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
 {
 	struct vfio_platform_region *reg = &vdev->regions[0];
 
+	dev_err_once(vdev->device, "DEPRECATION: VFIO Calxeda xgmac platform reset is deprecated and will be removed in a future kernel release\n");
+
 	if (!reg->ioaddr) {
 		reg->ioaddr =
 			ioremap(reg->addr, reg->size);
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
index ff8ff8480968..9f5c527baa8a 100644
--- a/drivers/vfio/platform/vfio_amba.c
+++ b/drivers/vfio/platform/vfio_amba.c
@@ -70,6 +70,8 @@ static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id)
 	struct vfio_platform_device *vdev;
 	int ret;
 
+	dev_err_once(&adev->dev, "DEPRECATION: vfio-amba is deprecated and will be removed in a future kernel release\n");
+
 	vdev = vfio_alloc_device(vfio_platform_device, vdev, &adev->dev,
 				 &vfio_amba_ops);
 	if (IS_ERR(vdev))
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 5046cae05222..38c8e9350a60 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -28,6 +28,7 @@
 #include <linux/pseudo_fs.h>
 #include <linux/rwsem.h>
 #include <linux/sched.h>
+#include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/stat.h>
 #include <linux/string.h>
@@ -1251,7 +1252,7 @@ static int vfio_ioctl_device_feature(struct vfio_device *device,
 			feature.argsz - minsz);
 	default:
 		if (unlikely(!device->ops->device_feature))
-			return -EINVAL;
+			return -ENOTTY;
 		return device->ops->device_feature(device, feature.flags,
 						   arg->data,
 						   feature.argsz - minsz);
@@ -1355,6 +1356,22 @@ static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
 	return device->ops->mmap(device, vma);
 }
 
+#ifdef CONFIG_PROC_FS
+static void vfio_device_show_fdinfo(struct seq_file *m, struct file *filep)
+{
+	char *path;
+	struct vfio_device_file *df = filep->private_data;
+	struct vfio_device *device = df->device;
+
+	path = kobject_get_path(&device->dev->kobj, GFP_KERNEL);
+	if (!path)
+		return;
+
+	seq_printf(m, "vfio-device-syspath: /sys%s\n", path);
+	kfree(path);
+}
+#endif
+
 const struct file_operations vfio_device_fops = {
 	.owner		= THIS_MODULE,
 	.open		= vfio_device_fops_cdev_open,
@@ -1364,6 +1381,9 @@ const struct file_operations vfio_device_fops = {
 	.unlocked_ioctl	= vfio_device_fops_unl_ioctl,
 	.compat_ioctl	= compat_ptr_ioctl,
 	.mmap		= vfio_device_fops_mmap,
+#ifdef CONFIG_PROC_FS
+	.show_fdinfo	= vfio_device_show_fdinfo,
+#endif
 };
 
 static struct vfio_device *vfio_device_from_file(struct file *file)