drm/xe/pf: Restrict device query responses in admin-only PF mode

When a PF is configured in admin-only mode, it is intended for management
only and must not expose workload-facing capabilities to userspace.

Limit the exposed ioctl set in admin-only PF mode to XE_DEVICE_QUERY and
XE_OBSERVATION, and suppress capability-bearing query payloads so that
the userspace cannot discover execution-related device details in this
mode.

Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Piotr Piórkowski <piotr.piorkowski@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Dunajski Bartosz <bartosz.dunajski@intel.com>
Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20260409154423.2499340-5-satyanarayana.k.v.p@intel.com

drivers/gpu/drm/xe/xe_device.c

@@ -25,6 +25,7 @@
 #include "regs/xe_regs.h"
 #include "xe_bo.h"
 #include "xe_bo_evict.h"
+#include "xe_configfs.h"
 #include "xe_debugfs.h"
 #include "xe_defaults.h"
 #include "xe_devcoredump.h"
@@ -390,7 +391,7 @@ bool xe_is_xe_file(const struct file *file)
 	return file->f_op == &xe_driver_fops;
 }
 
-static struct drm_driver driver = {
+static struct drm_driver regular_driver = {
 	.driver_features =
 	    DRIVER_GEM |
 	    DRIVER_RENDER | DRIVER_SYNCOBJ |
@@ -415,6 +416,39 @@ static struct drm_driver driver = {
 	.patchlevel = DRIVER_PATCHLEVEL,
 };
 
+#ifdef CONFIG_PCI_IOV
+static const struct drm_ioctl_desc xe_ioctls_admin_only[] = {
+	DRM_IOCTL_DEF_DRV(XE_DEVICE_QUERY, xe_query_ioctl, DRM_RENDER_ALLOW),
+	DRM_IOCTL_DEF_DRV(XE_OBSERVATION, xe_observation_ioctl, DRM_RENDER_ALLOW),
+};
+
+static struct drm_driver admin_only_driver = {
+	.driver_features =
+	    DRIVER_GEM | DRIVER_RENDER | DRIVER_GEM_GPUVA,
+	.open = xe_file_open,
+	.postclose = xe_file_close,
+	.ioctls = xe_ioctls_admin_only,
+	.num_ioctls = ARRAY_SIZE(xe_ioctls_admin_only),
+	.fops = &xe_driver_fops,
+	.name = DRIVER_NAME,
+	.desc = DRIVER_DESC,
+	.major = DRIVER_MAJOR,
+	.minor = DRIVER_MINOR,
+	.patchlevel = DRIVER_PATCHLEVEL,
+};
+
+/**
+ * xe_device_is_admin_only() - Check whether device is admin only or not.
+ * @xe: the &xe_device to check
+ *
+ * Return: true if the device is admin only, false otherwise.
+ */
+bool xe_device_is_admin_only(const struct xe_device *xe)
+{
+	return xe->drm.driver == &admin_only_driver;
+}
+#endif
+
 static void xe_device_destroy(struct drm_device *dev, void *dummy)
 {
 	struct xe_device *xe = to_xe_device(dev);
@@ -439,16 +473,26 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy)
 struct xe_device *xe_device_create(struct pci_dev *pdev,
 				   const struct pci_device_id *ent)
 {
+	struct drm_driver *driver = &regular_driver;
 	struct xe_device *xe;
 	int err;
 
-	xe_display_driver_set_hooks(&driver);
+#ifdef CONFIG_PCI_IOV
+	/*
+	 * Since XE device is not initialized yet, read from configfs
+	 * directly to decide whether we are in admin-only PF mode or not.
+	 */
+	if (xe_configfs_admin_only_pf(pdev))
+		driver = &admin_only_driver;
+#endif
 
-	err = aperture_remove_conflicting_pci_devices(pdev, driver.name);
+	xe_display_driver_set_hooks(driver);
+
+	err = aperture_remove_conflicting_pci_devices(pdev, driver->name);
 	if (err)
 		return ERR_PTR(err);
 
-	xe = devm_drm_dev_alloc(&pdev->dev, &driver, struct xe_device, drm);
+	xe = devm_drm_dev_alloc(&pdev->dev, driver, struct xe_device, drm);
 	if (IS_ERR(xe))
 		return xe;
 
@@ -708,6 +752,11 @@ int xe_device_probe_early(struct xe_device *xe)
 
 	xe_sriov_probe_early(xe);
 
+	if (xe_device_is_admin_only(xe) && !IS_SRIOV_PF(xe)) {
+		xe_err(xe, "Can't run Admin-only mode without SR-IOV PF mode!\n");
+		return -ENODEV;
+	}
+
 	if (IS_SRIOV_VF(xe))
 		vf_update_device_info(xe);
 

drivers/gpu/drm/xe/xe_device.h

@@ -211,6 +211,15 @@ bool xe_is_xe_file(const struct file *file);
 
 struct xe_vm *xe_device_asid_to_vm(struct xe_device *xe, u32 asid);
 
+#ifdef CONFIG_PCI_IOV
+bool xe_device_is_admin_only(const struct xe_device *xe);
+#else
+static inline bool xe_device_is_admin_only(const struct xe_device *xe)
+{
+	return false;
+}
+#endif
+
 /*
  * Occasionally it is seen that the G2H worker starts running after a delay of more than
  * a second even after being queued and activated by the Linux workqueue subsystem. This

drivers/gpu/drm/xe/xe_hw_engine.c

@@ -1026,6 +1026,9 @@ bool xe_hw_engine_is_reserved(struct xe_hw_engine *hwe)
 	struct xe_gt *gt = hwe->gt;
 	struct xe_device *xe = gt_to_xe(gt);
 
+	if (xe_device_is_admin_only(xe))
+		return true;
+
 	if (hwe->class == XE_ENGINE_CLASS_OTHER)
 		return true;
 

drivers/gpu/drm/xe/xe_query.c

@@ -231,6 +231,9 @@ static size_t calc_mem_regions_size(struct xe_device *xe)
 	u32 num_managers = 1;
 	int i;
 
+	if (xe_device_is_admin_only(xe))
+		return sizeof(struct drm_xe_query_mem_regions);
+
 	for (i = XE_PL_VRAM0; i <= XE_PL_VRAM1; ++i)
 		if (ttm_manager_type(&xe->ttm, i))
 			num_managers++;
@@ -259,6 +262,9 @@ static int query_mem_regions(struct xe_device *xe,
 	if (XE_IOCTL_DBG(xe, !mem_regions))
 		return -ENOMEM;
 
+	if (xe_device_is_admin_only(xe))
+		goto user_copy;
+
 	man = ttm_manager_type(&xe->ttm, XE_PL_TT);
 	mem_regions->mem_regions[0].mem_class = DRM_XE_MEM_REGION_CLASS_SYSMEM;
 	/*
@@ -297,6 +303,7 @@ static int query_mem_regions(struct xe_device *xe,
 		}
 	}
 
+user_copy:
 	if (!copy_to_user(query_ptr, mem_regions, size))
 		ret = 0;
 	else