Merge tag 'gvt-next-2017-08-15' of https://github.com/01org/gvt-linux into drm-intel-next-queued

gvt-next-2017-08-15

gvt update for 4.14
- MMIO save/restore optimization (Changbin)
- Split workload scan vs. dispatch for more parallel exec (Ping)
- vGPU full 48bit ppgtt support (Joonas, Tina)
- vGPU hw id expose for perf (Zhenyu)
- other misc cleanup and fixes

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815023940.skhjfcsyrao7axqi@zhen-hp.sh.intel.com

18 files changed, 297 insertions, 133 deletions

diff --git a/drivers/gpu/drm/i915/gvt/aperture_gm.c b/drivers/gpu/drm/i915/gvt/aperture_gm.c
index 325618d969fe..ca3d1925beda 100644
--- a/drivers/gpu/drm/i915/gvt/aperture_gm.c
+++ b/drivers/gpu/drm/i915/gvt/aperture_gm.c
@@ -285,8 +285,8 @@ static int alloc_resource(struct intel_vgpu *vgpu,
 	return 0;
 
 no_enough_resource:
-	gvt_vgpu_err("fail to allocate resource %s\n", item);
-	gvt_vgpu_err("request %luMB avail %luMB max %luMB taken %luMB\n",
+	gvt_err("fail to allocate resource %s\n", item);
+	gvt_err("request %luMB avail %luMB max %luMB taken %luMB\n",
 		BYTES_TO_MB(request), BYTES_TO_MB(avail),
 		BYTES_TO_MB(max), BYTES_TO_MB(taken));
 	return -ENOSPC;
diff --git a/drivers/gpu/drm/i915/gvt/cmd_parser.c b/drivers/gpu/drm/i915/gvt/cmd_parser.c
index 713848c36349..72b97ce525e8 100644
--- a/drivers/gpu/drm/i915/gvt/cmd_parser.c
+++ b/drivers/gpu/drm/i915/gvt/cmd_parser.c
@@ -1382,13 +1382,13 @@ static inline int cmd_address_audit(struct parser_exec_state *s,
 			ret = -EINVAL;
 			goto err;
 		}
-	} else if ((!vgpu_gmadr_is_valid(s->vgpu, guest_gma)) ||
-			(!vgpu_gmadr_is_valid(s->vgpu,
-					      guest_gma + op_size - 1))) {
+	} else if (!intel_gvt_ggtt_validate_range(vgpu, guest_gma, op_size)) {
 		ret = -EINVAL;
 		goto err;
 	}
+
 	return 0;
+
 err:
 	gvt_vgpu_err("cmd_parser: Malicious %s detected, addr=0x%lx, len=%d!\n",
 			s->info->name, guest_gma, op_size);
@@ -2647,7 +2647,7 @@ static int shadow_workload_ring_buffer(struct intel_vgpu_workload *workload)
 	return 0;
 }
 
-int intel_gvt_scan_and_shadow_workload(struct intel_vgpu_workload *workload)
+int intel_gvt_scan_and_shadow_ringbuffer(struct intel_vgpu_workload *workload)
 {
 	int ret;
 	struct intel_vgpu *vgpu = workload->vgpu;
diff --git a/drivers/gpu/drm/i915/gvt/cmd_parser.h b/drivers/gpu/drm/i915/gvt/cmd_parser.h
index bed33514103c..286703643002 100644
--- a/drivers/gpu/drm/i915/gvt/cmd_parser.h
+++ b/drivers/gpu/drm/i915/gvt/cmd_parser.h
@@ -42,7 +42,7 @@ void intel_gvt_clean_cmd_parser(struct intel_gvt *gvt);
 
 int intel_gvt_init_cmd_parser(struct intel_gvt *gvt);
 
-int intel_gvt_scan_and_shadow_workload(struct intel_vgpu_workload *workload);
+int intel_gvt_scan_and_shadow_ringbuffer(struct intel_vgpu_workload *workload);
 
 int intel_gvt_scan_and_shadow_wa_ctx(struct intel_shadow_wa_ctx *wa_ctx);
 
diff --git a/drivers/gpu/drm/i915/gvt/execlist.c b/drivers/gpu/drm/i915/gvt/execlist.c
index 700050556242..df11f69edc05 100644
--- a/drivers/gpu/drm/i915/gvt/execlist.c
+++ b/drivers/gpu/drm/i915/gvt/execlist.c
@@ -605,6 +605,7 @@ static int submit_context(struct intel_vgpu *vgpu, int ring_id,
 	struct list_head *q = workload_q_head(vgpu, ring_id);
 	struct intel_vgpu_workload *last_workload = get_last_workload(q);
 	struct intel_vgpu_workload *workload = NULL;
+	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
 	u64 ring_context_gpa;
 	u32 head, tail, start, ctl, ctx_ctl, per_ctx, indirect_ctx;
 	int ret;
@@ -668,6 +669,7 @@ static int submit_context(struct intel_vgpu *vgpu, int ring_id,
 	workload->complete = complete_execlist_workload;
 	workload->status = -EINPROGRESS;
 	workload->emulate_schedule_in = emulate_schedule_in;
+	workload->shadowed = false;
 
 	if (ring_id == RCS) {
 		intel_gvt_hypervisor_read_gpa(vgpu, ring_context_gpa +
@@ -701,6 +703,17 @@ static int submit_context(struct intel_vgpu *vgpu, int ring_id,
 		return ret;
 	}
 
+	/* Only scan and shadow the first workload in the queue
+	 * as there is only one pre-allocated buf-obj for shadow.
+	 */
+	if (list_empty(workload_q_head(vgpu, ring_id))) {
+		intel_runtime_pm_get(dev_priv);
+		mutex_lock(&dev_priv->drm.struct_mutex);
+		intel_gvt_scan_and_shadow_workload(workload);
+		mutex_unlock(&dev_priv->drm.struct_mutex);
+		intel_runtime_pm_put(dev_priv);
+	}
+
 	queue_workload(workload);
 	return 0;
 }
@@ -783,6 +796,8 @@ static void clean_workloads(struct intel_vgpu *vgpu, unsigned long engine_mask)
 			list_del_init(&pos->list);
 			free_workload(pos);
 		}
+
+		clear_bit(engine->id, vgpu->shadow_ctx_desc_updated);
 	}
 }
 
diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index 6166e34d892b..e6dfc3331f4b 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -259,7 +259,7 @@ static void write_pte64(struct drm_i915_private *dev_priv,
 	writeq(pte, addr);
 }
 
-static inline struct intel_gvt_gtt_entry *gtt_get_entry64(void *pt,
+static inline int gtt_get_entry64(void *pt,
 		struct intel_gvt_gtt_entry *e,
 		unsigned long index, bool hypervisor_access, unsigned long gpa,
 		struct intel_vgpu *vgpu)
@@ -268,22 +268,23 @@ static inline struct intel_gvt_gtt_entry *gtt_get_entry64(void *pt,
 	int ret;
 
 	if (WARN_ON(info->gtt_entry_size != 8))
-		return e;
+		return -EINVAL;
 
 	if (hypervisor_access) {
 		ret = intel_gvt_hypervisor_read_gpa(vgpu, gpa +
 				(index << info->gtt_entry_size_shift),
 				&e->val64, 8);
-		WARN_ON(ret);
+		if (WARN_ON(ret))
+			return ret;
 	} else if (!pt) {
 		e->val64 = read_pte64(vgpu->gvt->dev_priv, index);
 	} else {
 		e->val64 = *((u64 *)pt + index);
 	}
-	return e;
+	return 0;
 }
 
-static inline struct intel_gvt_gtt_entry *gtt_set_entry64(void *pt,
+static inline int gtt_set_entry64(void *pt,
 		struct intel_gvt_gtt_entry *e,
 		unsigned long index, bool hypervisor_access, unsigned long gpa,
 		struct intel_vgpu *vgpu)
@@ -292,19 +293,20 @@ static inline struct intel_gvt_gtt_entry *gtt_set_entry64(void *pt,
 	int ret;
 
 	if (WARN_ON(info->gtt_entry_size != 8))
-		return e;
+		return -EINVAL;
 
 	if (hypervisor_access) {
 		ret = intel_gvt_hypervisor_write_gpa(vgpu, gpa +
 				(index << info->gtt_entry_size_shift),
 				&e->val64, 8);
-		WARN_ON(ret);
+		if (WARN_ON(ret))
+			return ret;
 	} else if (!pt) {
 		write_pte64(vgpu->gvt->dev_priv, index, e->val64);
 	} else {
 		*((u64 *)pt + index) = e->val64;
 	}
-	return e;
+	return 0;
 }
 
 #define GTT_HAW 46
@@ -445,21 +447,25 @@ static int gtt_entry_p2m(struct intel_vgpu *vgpu, struct intel_gvt_gtt_entry *p,
 /*
  * MM helpers.
  */
-struct intel_gvt_gtt_entry *intel_vgpu_mm_get_entry(struct intel_vgpu_mm *mm,
+int intel_vgpu_mm_get_entry(struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index)
 {
 	struct intel_gvt *gvt = mm->vgpu->gvt;
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
+	int ret;
 
 	e->type = mm->page_table_entry_type;
 
-	ops->get_entry(page_table, e, index, false, 0, mm->vgpu);
+	ret = ops->get_entry(page_table, e, index, false, 0, mm->vgpu);
+	if (ret)
+		return ret;
+
 	ops->test_pse(e);
-	return e;
+	return 0;
 }
 
-struct intel_gvt_gtt_entry *intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
+int intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index)
 {
@@ -472,7 +478,7 @@ struct intel_gvt_gtt_entry *intel_vgpu_mm_set_entry(struct intel_vgpu_mm *mm,
 /*
  * PPGTT shadow page table helpers.
  */
-static inline struct intel_gvt_gtt_entry *ppgtt_spt_get_entry(
+static inline int ppgtt_spt_get_entry(
 		struct intel_vgpu_ppgtt_spt *spt,
 		void *page_table, int type,
 		struct intel_gvt_gtt_entry *e, unsigned long index,
@@ -480,20 +486,24 @@ static inline struct intel_gvt_gtt_entry *ppgtt_spt_get_entry(
 {
 	struct intel_gvt *gvt = spt->vgpu->gvt;
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
+	int ret;
 
 	e->type = get_entry_type(type);
 
 	if (WARN(!gtt_type_is_entry(e->type), "invalid entry type\n"))
-		return e;
+		return -EINVAL;
 
-	ops->get_entry(page_table, e, index, guest,
+	ret = ops->get_entry(page_table, e, index, guest,
 			spt->guest_page.gfn << GTT_PAGE_SHIFT,
 			spt->vgpu);
+	if (ret)
+		return ret;
+
 	ops->test_pse(e);
-	return e;
+	return 0;
 }
 
-static inline struct intel_gvt_gtt_entry *ppgtt_spt_set_entry(
+static inline int ppgtt_spt_set_entry(
 		struct intel_vgpu_ppgtt_spt *spt,
 		void *page_table, int type,
 		struct intel_gvt_gtt_entry *e, unsigned long index,
@@ -503,7 +513,7 @@ static inline struct intel_gvt_gtt_entry *ppgtt_spt_set_entry(
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
 
 	if (WARN(!gtt_type_is_entry(e->type), "invalid entry type\n"))
-		return e;
+		return -EINVAL;
 
 	return ops->set_entry(page_table, e, index, guest,
 			spt->guest_page.gfn << GTT_PAGE_SHIFT,
@@ -792,13 +802,13 @@ static struct intel_vgpu_ppgtt_spt *ppgtt_find_shadow_page(
 
 #define for_each_present_guest_entry(spt, e, i) \
 	for (i = 0; i < pt_entries(spt); i++) \
-	if (spt->vgpu->gvt->gtt.pte_ops->test_present( \
-		ppgtt_get_guest_entry(spt, e, i)))
+		if (!ppgtt_get_guest_entry(spt, e, i) && \
+		    spt->vgpu->gvt->gtt.pte_ops->test_present(e))
 
 #define for_each_present_shadow_entry(spt, e, i) \
 	for (i = 0; i < pt_entries(spt); i++) \
-	if (spt->vgpu->gvt->gtt.pte_ops->test_present( \
-		ppgtt_get_shadow_entry(spt, e, i)))
+		if (!ppgtt_get_shadow_entry(spt, e, i) && \
+		    spt->vgpu->gvt->gtt.pte_ops->test_present(e))
 
 static void ppgtt_get_shadow_page(struct intel_vgpu_ppgtt_spt *spt)
 {
@@ -979,29 +989,26 @@ fail:
 }
 
 static int ppgtt_handle_guest_entry_removal(struct intel_vgpu_guest_page *gpt,
-		unsigned long index)
+		struct intel_gvt_gtt_entry *se, unsigned long index)
 {
 	struct intel_vgpu_ppgtt_spt *spt = guest_page_to_ppgtt_spt(gpt);
 	struct intel_vgpu_shadow_page *sp = &spt->shadow_page;
 	struct intel_vgpu *vgpu = spt->vgpu;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
-	struct intel_gvt_gtt_entry e;
 	int ret;
 
-	ppgtt_get_shadow_entry(spt, &e, index);
-
-	trace_gpt_change(spt->vgpu->id, "remove", spt, sp->type, e.val64,
+	trace_gpt_change(spt->vgpu->id, "remove", spt, sp->type, se->val64,
 			 index);
 
-	if (!ops->test_present(&e))
+	if (!ops->test_present(se))
 		return 0;
 
-	if (ops->get_pfn(&e) == vgpu->gtt.scratch_pt[sp->type].page_mfn)
+	if (ops->get_pfn(se) == vgpu->gtt.scratch_pt[sp->type].page_mfn)
 		return 0;
 
-	if (gtt_type_is_pt(get_next_pt_type(e.type))) {
+	if (gtt_type_is_pt(get_next_pt_type(se->type))) {
 		struct intel_vgpu_ppgtt_spt *s =
-			ppgtt_find_shadow_page(vgpu, ops->get_pfn(&e));
+			ppgtt_find_shadow_page(vgpu, ops->get_pfn(se));
 		if (!s) {
 			gvt_vgpu_err("fail to find guest page\n");
 			ret = -ENXIO;
@@ -1011,12 +1018,10 @@ static int ppgtt_handle_guest_entry_removal(struct intel_vgpu_guest_page *gpt,
 		if (ret)
 			goto fail;
 	}
-	ops->set_pfn(&e, vgpu->gtt.scratch_pt[sp->type].page_mfn);
-	ppgtt_set_shadow_entry(spt, &e, index);
 	return 0;
 fail:
 	gvt_vgpu_err("fail: shadow page %p guest entry 0x%llx type %d\n",
-			spt, e.val64, e.type);
+			spt, se->val64, se->type);
 	return ret;
 }
 
@@ -1236,22 +1241,37 @@ static int ppgtt_handle_guest_write_page_table(
 {
 	struct intel_vgpu_ppgtt_spt *spt = guest_page_to_ppgtt_spt(gpt);
 	struct intel_vgpu *vgpu = spt->vgpu;
+	int type = spt->shadow_page.type;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
+	struct intel_gvt_gtt_entry se;
 
 	int ret;
 	int new_present;
 
 	new_present = ops->test_present(we);
 
-	ret = ppgtt_handle_guest_entry_removal(gpt, index);
-	if (ret)
-		goto fail;
+	/*
+	 * Adding the new entry first and then removing the old one, that can
+	 * guarantee the ppgtt table is validated during the window between
+	 * adding and removal.
+	 */
+	ppgtt_get_shadow_entry(spt, &se, index);
 
 	if (new_present) {
 		ret = ppgtt_handle_guest_entry_add(gpt, we, index);
 		if (ret)
 			goto fail;
 	}
+
+	ret = ppgtt_handle_guest_entry_removal(gpt, &se, index);
+	if (ret)
+		goto fail;
+
+	if (!new_present) {
+		ops->set_pfn(&se, vgpu->gtt.scratch_pt[type].page_mfn);
+		ppgtt_set_shadow_entry(spt, &se, index);
+	}
+
 	return 0;
 fail:
 	gvt_vgpu_err("fail: shadow page %p guest entry 0x%llx type %d.\n",
@@ -1323,7 +1343,7 @@ static int ppgtt_handle_guest_write_page_table_bytes(void *gp,
 	struct intel_vgpu *vgpu = spt->vgpu;
 	struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
 	const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
-	struct intel_gvt_gtt_entry we;
+	struct intel_gvt_gtt_entry we, se;
 	unsigned long index;
 	int ret;
 
@@ -1339,7 +1359,8 @@ static int ppgtt_handle_guest_write_page_table_bytes(void *gp,
 			return ret;
 	} else {
 		if (!test_bit(index, spt->post_shadow_bitmap)) {
-			ret = ppgtt_handle_guest_entry_removal(gpt, index);
+			ppgtt_get_shadow_entry(spt, &se, index);
+			ret = ppgtt_handle_guest_entry_removal(gpt, &se, index);
 			if (ret)
 				return ret;
 		}
@@ -1713,8 +1734,10 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 		if (!vgpu_gmadr_is_valid(vgpu, gma))
 			goto err;
 
-		ggtt_get_guest_entry(mm, &e,
-			gma_ops->gma_to_ggtt_pte_index(gma));
+		ret = ggtt_get_guest_entry(mm, &e,
+				gma_ops->gma_to_ggtt_pte_index(gma));
+		if (ret)
+			goto err;
 		gpa = (pte_ops->get_pfn(&e) << GTT_PAGE_SHIFT)
 			+ (gma & ~GTT_PAGE_MASK);
 
@@ -1724,7 +1747,9 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 
 	switch (mm->page_table_level) {
 	case 4:
-		ppgtt_get_shadow_root_entry(mm, &e, 0);
+		ret = ppgtt_get_shadow_root_entry(mm, &e, 0);
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pml4_index(gma);
 		gma_index[1] = gma_ops->gma_to_l4_pdp_index(gma);
 		gma_index[2] = gma_ops->gma_to_pde_index(gma);
@@ -1732,15 +1757,19 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 		index = 4;
 		break;
 	case 3:
-		ppgtt_get_shadow_root_entry(mm, &e,
+		ret = ppgtt_get_shadow_root_entry(mm, &e,
 				gma_ops->gma_to_l3_pdp_index(gma));
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pde_index(gma);
 		gma_index[1] = gma_ops->gma_to_pte_index(gma);
 		index = 2;
 		break;
 	case 2:
-		ppgtt_get_shadow_root_entry(mm, &e,
+		ret = ppgtt_get_shadow_root_entry(mm, &e,
 				gma_ops->gma_to_pde_index(gma));
+		if (ret)
+			goto err;
 		gma_index[0] = gma_ops->gma_to_pte_index(gma);
 		index = 1;
 		break;
@@ -1755,6 +1784,11 @@ unsigned long intel_vgpu_gma_to_gpa(struct intel_vgpu_mm *mm, unsigned long gma)
 			(i == index - 1));
 		if (ret)
 			goto err;
+
+		if (!pte_ops->test_present(&e)) {
+			gvt_dbg_core("GMA 0x%lx is not present\n", gma);
+			goto err;
+		}
 	}
 
 	gpa = (pte_ops->get_pfn(&e) << GTT_PAGE_SHIFT)
@@ -2329,13 +2363,12 @@ void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu)
 /**
  * intel_vgpu_reset_gtt - reset the all GTT related status
  * @vgpu: a vGPU
- * @dmlr: true for vGPU Device Model Level Reset, false for GT Reset
  *
  * This function is called from vfio core to reset reset all
  * GTT related status, including GGTT, PPGTT, scratch page.
  *
  */
-void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr)
+void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu)
 {
 	int i;
 
@@ -2347,9 +2380,6 @@ void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr)
 	 */
 	intel_vgpu_free_mm(vgpu, INTEL_GVT_MM_PPGTT);
 
-	if (!dmlr)
-		return;
-
 	intel_vgpu_reset_ggtt(vgpu);
 
 	/* clear scratch page for security */
diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
index f88eb5e89bea..30a4c8d16026 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.h
+++ b/drivers/gpu/drm/i915/gvt/gtt.h
@@ -49,14 +49,18 @@ struct intel_gvt_gtt_entry {
 };
 
 struct intel_gvt_gtt_pte_ops {
-	struct intel_gvt_gtt_entry *(*get_entry)(void *pt,
-		struct intel_gvt_gtt_entry *e,
-		unsigned long index, bool hypervisor_access, unsigned long gpa,
-		struct intel_vgpu *vgpu);
-	struct intel_gvt_gtt_entry *(*set_entry)(void *pt,
-		struct intel_gvt_gtt_entry *e,
-		unsigned long index, bool hypervisor_access, unsigned long gpa,
-		struct intel_vgpu *vgpu);
+	int (*get_entry)(void *pt,
+			 struct intel_gvt_gtt_entry *e,
+			 unsigned long index,
+			 bool hypervisor_access,
+			 unsigned long gpa,
+			 struct intel_vgpu *vgpu);
+	int (*set_entry)(void *pt,
+			 struct intel_gvt_gtt_entry *e,
+			 unsigned long index,
+			 bool hypervisor_access,
+			 unsigned long gpa,
+			 struct intel_vgpu *vgpu);
 	bool (*test_present)(struct intel_gvt_gtt_entry *e);
 	void (*clear_present)(struct intel_gvt_gtt_entry *e);
 	bool (*test_pse)(struct intel_gvt_gtt_entry *e);
@@ -143,12 +147,12 @@ struct intel_vgpu_mm {
 	struct intel_vgpu *vgpu;
 };
 
-extern struct intel_gvt_gtt_entry *intel_vgpu_mm_get_entry(
+extern int intel_vgpu_mm_get_entry(
 		struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index);
 
-extern struct intel_gvt_gtt_entry *intel_vgpu_mm_set_entry(
+extern int intel_vgpu_mm_set_entry(
 		struct intel_vgpu_mm *mm,
 		void *page_table, struct intel_gvt_gtt_entry *e,
 		unsigned long index);
@@ -208,7 +212,7 @@ extern void intel_vgpu_clean_gtt(struct intel_vgpu *vgpu);
 void intel_vgpu_reset_ggtt(struct intel_vgpu *vgpu);
 
 extern int intel_gvt_init_gtt(struct intel_gvt *gvt);
-extern void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu, bool dmlr);
+void intel_vgpu_reset_gtt(struct intel_vgpu *vgpu);
 extern void intel_gvt_clean_gtt(struct intel_gvt *gvt);
 
 extern struct intel_vgpu_mm *intel_gvt_find_ppgtt_mm(struct intel_vgpu *vgpu,
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 3a74e79eac2f..ea736717e051 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -167,6 +167,7 @@ struct intel_vgpu {
 	atomic_t running_workload_num;
 	DECLARE_BITMAP(tlb_handle_pending, I915_NUM_ENGINES);
 	struct i915_gem_context *shadow_ctx;
+	DECLARE_BITMAP(shadow_ctx_desc_updated, I915_NUM_ENGINES);
 
 #if IS_ENABLED(CONFIG_DRM_I915_GVT_KVMGT)
 	struct {
@@ -470,6 +471,8 @@ int intel_vgpu_init_opregion(struct intel_vgpu *vgpu, u32 gpa);
 int intel_vgpu_emulate_opregion_request(struct intel_vgpu *vgpu, u32 swsci);
 void populate_pvinfo_page(struct intel_vgpu *vgpu);
 
+int intel_gvt_scan_and_shadow_workload(struct intel_vgpu_workload *workload);
+
 struct intel_gvt_ops {
 	int (*emulate_cfg_read)(struct intel_vgpu *, unsigned int, void *,
 				unsigned int);
diff --git a/drivers/gpu/drm/i915/gvt/handlers.c b/drivers/gpu/drm/i915/gvt/handlers.c
index aeecf315c5db..d85264d48585 100644
--- a/drivers/gpu/drm/i915/gvt/handlers.c
+++ b/drivers/gpu/drm/i915/gvt/handlers.c
@@ -113,9 +113,17 @@ static int new_mmio_info(struct intel_gvt *gvt,
 
 		info->offset = i;
 		p = find_mmio_info(gvt, info->offset);
-		if (p)
-			gvt_err("dup mmio definition offset %x\n",
+		if (p) {
+			WARN(1, "dup mmio definition offset %x\n",
 				info->offset);
+			kfree(info);
+
+			/* We return -EEXIST here to make GVT-g load fail.
+			 * So duplicated MMIO can be found as soon as
+			 * possible.
+			 */
+			return -EEXIST;
+		}
 
 		info->ro_mask = ro_mask;
 		info->device = device;
@@ -2583,7 +2591,6 @@ static int init_broadwell_mmio_info(struct intel_gvt *gvt)
 	MMIO_F(0x24d0, 48, F_CMD_ACCESS, 0, 0, D_BDW_PLUS,
 		NULL, force_nonpriv_write);
 
-	MMIO_D(0x22040, D_BDW_PLUS);
 	MMIO_D(0x44484, D_BDW_PLUS);
 	MMIO_D(0x4448c, D_BDW_PLUS);
 
@@ -2641,7 +2648,6 @@ static int init_skl_mmio_info(struct intel_gvt *gvt)
 	MMIO_D(HSW_PWR_WELL_BIOS, D_SKL_PLUS);
 	MMIO_DH(HSW_PWR_WELL_DRIVER, D_SKL_PLUS, NULL,
 						skl_power_well_ctl_write);
-	MMIO_DH(GEN6_PCODE_MAILBOX, D_SKL_PLUS, NULL, mailbox_write);
 
 	MMIO_D(0xa210, D_SKL_PLUS);
 	MMIO_D(GEN9_MEDIA_PG_IDLE_HYSTERESIS, D_SKL_PLUS);
@@ -2833,7 +2839,6 @@ static int init_skl_mmio_info(struct intel_gvt *gvt)
 	MMIO_D(0x320f0, D_SKL | D_KBL);
 
 	MMIO_DFH(_REG_VCS2_EXCC, D_SKL_PLUS, F_CMD_ACCESS, NULL, NULL);
-	MMIO_DFH(_REG_VECS_EXCC, D_SKL_PLUS, F_CMD_ACCESS, NULL, NULL);
 	MMIO_D(0x70034, D_SKL_PLUS);
 	MMIO_D(0x71034, D_SKL_PLUS);
 	MMIO_D(0x72034, D_SKL_PLUS);
@@ -2851,10 +2856,7 @@ static int init_skl_mmio_info(struct intel_gvt *gvt)
 		NULL, NULL);
 
 	MMIO_D(0x4ab8, D_KBL);
-	MMIO_D(0x940c, D_SKL_PLUS);
 	MMIO_D(0x2248, D_SKL_PLUS | D_KBL);
-	MMIO_D(0x4ab0, D_SKL | D_KBL);
-	MMIO_D(0x20d4, D_SKL | D_KBL);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index fd0c85f9ef3c..83e88c70272a 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1170,10 +1170,27 @@ vgpu_id_show(struct device *dev, struct device_attribute *attr,
 	return sprintf(buf, "\n");
 }
 
+static ssize_t
+hw_id_show(struct device *dev, struct device_attribute *attr,
+	   char *buf)
+{
+	struct mdev_device *mdev = mdev_from_dev(dev);
+
+	if (mdev) {
+		struct intel_vgpu *vgpu = (struct intel_vgpu *)
+			mdev_get_drvdata(mdev);
+		return sprintf(buf, "%u\n",
+			       vgpu->shadow_ctx->hw_id);
+	}
+	return sprintf(buf, "\n");
+}
+
 static DEVICE_ATTR_RO(vgpu_id);
+static DEVICE_ATTR_RO(hw_id);
 
 static struct attribute *intel_vgpu_attrs[] = {
 	&dev_attr_vgpu_id.attr,
+	&dev_attr_hw_id.attr,
 	NULL
 };
 
diff --git a/drivers/gpu/drm/i915/gvt/render.c b/drivers/gpu/drm/i915/gvt/render.c
index 504e57c3bc23..2ea542257f03 100644
--- a/drivers/gpu/drm/i915/gvt/render.c
+++ b/drivers/gpu/drm/i915/gvt/render.c
@@ -207,18 +207,16 @@ static void load_mocs(struct intel_vgpu *vgpu, int ring_id)
 
 	offset.reg = regs[ring_id];
 	for (i = 0; i < 64; i++) {
-		gen9_render_mocs[ring_id][i] = I915_READ(offset);
+		gen9_render_mocs[ring_id][i] = I915_READ_FW(offset);
 		I915_WRITE(offset, vgpu_vreg(vgpu, offset));
-		POSTING_READ(offset);
 		offset.reg += 4;
 	}
 
 	if (ring_id == RCS) {
 		l3_offset.reg = 0xb020;
 		for (i = 0; i < 32; i++) {
-			gen9_render_mocs_L3[i] = I915_READ(l3_offset);
-			I915_WRITE(l3_offset, vgpu_vreg(vgpu, l3_offset));
-			POSTING_READ(l3_offset);
+			gen9_render_mocs_L3[i] = I915_READ_FW(l3_offset);
+			I915_WRITE_FW(l3_offset, vgpu_vreg(vgpu, l3_offset));
 			l3_offset.reg += 4;
 		}
 	}
@@ -242,18 +240,16 @@ static void restore_mocs(struct intel_vgpu *vgpu, int ring_id)
 
 	offset.reg = regs[ring_id];
 	for (i = 0; i < 64; i++) {
-		vgpu_vreg(vgpu, offset) = I915_READ(offset);
-		I915_WRITE(offset, gen9_render_mocs[ring_id][i]);
-		POSTING_READ(offset);
+		vgpu_vreg(vgpu, offset) = I915_READ_FW(offset);
+		I915_WRITE_FW(offset, gen9_render_mocs[ring_id][i]);
 		offset.reg += 4;
 	}
 
 	if (ring_id == RCS) {
 		l3_offset.reg = 0xb020;
 		for (i = 0; i < 32; i++) {
-			vgpu_vreg(vgpu, l3_offset) = I915_READ(l3_offset);
-			I915_WRITE(l3_offset, gen9_render_mocs_L3[i]);
-			POSTING_READ(l3_offset);
+			vgpu_vreg(vgpu, l3_offset) = I915_READ_FW(l3_offset);
+			I915_WRITE_FW(l3_offset, gen9_render_mocs_L3[i]);
 			l3_offset.reg += 4;
 		}
 	}
@@ -272,6 +268,7 @@ static void switch_mmio_to_vgpu(struct intel_vgpu *vgpu, int ring_id)
 	u32 ctx_ctrl = reg_state[CTX_CONTEXT_CONTROL_VAL];
 	u32 inhibit_mask =
 		_MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);
+	i915_reg_t last_reg = _MMIO(0);
 
 	if (IS_SKYLAKE(vgpu->gvt->dev_priv)
 		|| IS_KABYLAKE(vgpu->gvt->dev_priv)) {
@@ -287,7 +284,7 @@ static void switch_mmio_to_vgpu(struct intel_vgpu *vgpu, int ring_id)
 		if (mmio->ring_id != ring_id)
 			continue;
 
-		mmio->value = I915_READ(mmio->reg);
+		mmio->value = I915_READ_FW(mmio->reg);
 
 		/*
 		 * if it is an inhibit context, load in_context mmio
@@ -304,13 +301,18 @@ static void switch_mmio_to_vgpu(struct intel_vgpu *vgpu, int ring_id)
 		else
 			v = vgpu_vreg(vgpu, mmio->reg);
 
-		I915_WRITE(mmio->reg, v);
-		POSTING_READ(mmio->reg);
+		I915_WRITE_FW(mmio->reg, v);
+		last_reg = mmio->reg;
 
 		trace_render_mmio(vgpu->id, "load",
 				  i915_mmio_reg_offset(mmio->reg),
 				  mmio->value, v);
 	}
+
+	/* Make sure the swiched MMIOs has taken effect. */
+	if (likely(INTEL_GVT_MMIO_OFFSET(last_reg)))
+		I915_READ_FW(last_reg);
+
 	handle_tlb_pending_event(vgpu, ring_id);
 }
 
@@ -319,6 +321,7 @@ static void switch_mmio_to_host(struct intel_vgpu *vgpu, int ring_id)
 {
 	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
 	struct render_mmio *mmio;
+	i915_reg_t last_reg = _MMIO(0);
 	u32 v;
 	int i, array_size;
 
@@ -335,7 +338,7 @@ static void switch_mmio_to_host(struct intel_vgpu *vgpu, int ring_id)
 		if (mmio->ring_id != ring_id)
 			continue;
 
-		vgpu_vreg(vgpu, mmio->reg) = I915_READ(mmio->reg);
+		vgpu_vreg(vgpu, mmio->reg) = I915_READ_FW(mmio->reg);
 
 		if (mmio->mask) {
 			vgpu_vreg(vgpu, mmio->reg) &= ~(mmio->mask << 16);
@@ -346,13 +349,17 @@ static void switch_mmio_to_host(struct intel_vgpu *vgpu, int ring_id)
 		if (mmio->in_context)
 			continue;
 
-		I915_WRITE(mmio->reg, v);
-		POSTING_READ(mmio->reg);
+		I915_WRITE_FW(mmio->reg, v);
+		last_reg = mmio->reg;
 
 		trace_render_mmio(vgpu->id, "restore",
 				  i915_mmio_reg_offset(mmio->reg),
 				  mmio->value, v);
 	}
+
+	/* Make sure the swiched MMIOs has taken effect. */
+	if (likely(INTEL_GVT_MMIO_OFFSET(last_reg)))
+		I915_READ_FW(last_reg);
 }
 
 /**
@@ -367,12 +374,23 @@ static void switch_mmio_to_host(struct intel_vgpu *vgpu, int ring_id)
 void intel_gvt_switch_mmio(struct intel_vgpu *pre,
 			   struct intel_vgpu *next, int ring_id)
 {
+	struct drm_i915_private *dev_priv;
+
 	if (WARN_ON(!pre && !next))
 		return;
 
 	gvt_dbg_render("switch ring %d from %s to %s\n", ring_id,
 		       pre ? "vGPU" : "host", next ? "vGPU" : "HOST");
 
+	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;
+
+	/**
+	 * We are using raw mmio access wrapper to improve the
+	 * performace for batch mmio read/write, so we need
+	 * handle forcewake mannually.
+	 */
+	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
+
 	/**
 	 * TODO: Optimize for vGPU to vGPU switch by merging
 	 * switch_mmio_to_host() and switch_mmio_to_vgpu().
@@ -382,4 +400,6 @@ void intel_gvt_switch_mmio(struct intel_vgpu *pre,
 
 	if (next)
 		switch_mmio_to_vgpu(next, ring_id);
+
+	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
 }
diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index 0e2e36ad6196..025aba8a72e0 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -184,41 +184,52 @@ static int shadow_context_status_change(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
-static int dispatch_workload(struct intel_vgpu_workload *workload)
+static void shadow_context_descriptor_update(struct i915_gem_context *ctx,
+		struct intel_engine_cs *engine)
+{
+	struct intel_context *ce = &ctx->engine[engine->id];
+	u64 desc = 0;
+
+	desc = ce->lrc_desc;
+
+	/* Update bits 0-11 of the context descriptor which includes flags
+	 * like GEN8_CTX_* cached in desc_template
+	 */
+	desc &= U64_MAX << 12;
+	desc |= ctx->desc_template & ((1ULL << 12) - 1);
+
+	ce->lrc_desc = desc;
+}
+
+/**
+ * intel_gvt_scan_and_shadow_workload - audit the workload by scanning and
+ * shadow it as well, include ringbuffer,wa_ctx and ctx.
+ * @workload: an abstract entity for each execlist submission.
+ *
+ * This function is called before the workload submitting to i915, to make
+ * sure the content of the workload is valid.
+ */
+int intel_gvt_scan_and_shadow_workload(struct intel_vgpu_workload *workload)
 {
 	int ring_id = workload->ring_id;
 	struct i915_gem_context *shadow_ctx = workload->vgpu->shadow_ctx;
 	struct drm_i915_private *dev_priv = workload->vgpu->gvt->dev_priv;
-	struct intel_engine_cs *engine = dev_priv->engine[ring_id];
 	struct drm_i915_gem_request *rq;
 	struct intel_vgpu *vgpu = workload->vgpu;
-	struct intel_ring *ring;
 	int ret;
 
-	gvt_dbg_sched("ring id %d prepare to dispatch workload %p\n",
-		ring_id, workload);
+	lockdep_assert_held(&dev_priv->drm.struct_mutex);
+
+	if (workload->shadowed)
+		return 0;
 
 	shadow_ctx->desc_template &= ~(0x3 << GEN8_CTX_ADDRESSING_MODE_SHIFT);
 	shadow_ctx->desc_template |= workload->ctx_desc.addressing_mode <<
 				    GEN8_CTX_ADDRESSING_MODE_SHIFT;
 
-	mutex_lock(&dev_priv->drm.struct_mutex);
-
-	/* pin shadow context by gvt even the shadow context will be pinned
-	 * when i915 alloc request. That is because gvt will update the guest
-	 * context from shadow context when workload is completed, and at that
-	 * moment, i915 may already unpined the shadow context to make the
-	 * shadow_ctx pages invalid. So gvt need to pin itself. After update
-	 * the guest context, gvt can unpin the shadow_ctx safely.
-	 */
-	ring = engine->context_pin(engine, shadow_ctx);
-	if (IS_ERR(ring)) {
-		ret = PTR_ERR(ring);
-		gvt_vgpu_err("fail to pin shadow context\n");
-		workload->status = ret;
-		mutex_unlock(&dev_priv->drm.struct_mutex);
-		return ret;
-	}
+	if (!test_and_set_bit(ring_id, vgpu->shadow_ctx_desc_updated))
+		shadow_context_descriptor_update(shadow_ctx,
+					dev_priv->engine[ring_id]);
 
 	rq = i915_gem_request_alloc(dev_priv->engine[ring_id], shadow_ctx);
 	if (IS_ERR(rq)) {
@@ -231,7 +242,7 @@ static int dispatch_workload(struct intel_vgpu_workload *workload)
 
 	workload->req = i915_gem_request_get(rq);
 
-	ret = intel_gvt_scan_and_shadow_workload(workload);
+	ret = intel_gvt_scan_and_shadow_ringbuffer(workload);
 	if (ret)
 		goto out;
 
@@ -246,25 +257,61 @@ static int dispatch_workload(struct intel_vgpu_workload *workload)
 	if (ret)
 		goto out;
 
+	workload->shadowed = true;
+
+out:
+	return ret;
+}
+
+static int dispatch_workload(struct intel_vgpu_workload *workload)
+{
+	int ring_id = workload->ring_id;
+	struct i915_gem_context *shadow_ctx = workload->vgpu->shadow_ctx;
+	struct drm_i915_private *dev_priv = workload->vgpu->gvt->dev_priv;
+	struct intel_engine_cs *engine = dev_priv->engine[ring_id];
+	struct intel_vgpu *vgpu = workload->vgpu;
+	struct intel_ring *ring;
+	int ret = 0;
+
+	gvt_dbg_sched("ring id %d prepare to dispatch workload %p\n",
+		ring_id, workload);
+
+	mutex_lock(&dev_priv->drm.struct_mutex);
+
+	ret = intel_gvt_scan_and_shadow_workload(workload);
+	if (ret)
+		goto out;
+
 	if (workload->prepare) {
 		ret = workload->prepare(workload);
 		if (ret)
 			goto out;
 	}
 
-	gvt_dbg_sched("ring id %d submit workload to i915 %p\n",
-			ring_id, workload->req);
+	/* pin shadow context by gvt even the shadow context will be pinned
+	 * when i915 alloc request. That is because gvt will update the guest
+	 * context from shadow context when workload is completed, and at that
+	 * moment, i915 may already unpined the shadow context to make the
+	 * shadow_ctx pages invalid. So gvt need to pin itself. After update
+	 * the guest context, gvt can unpin the shadow_ctx safely.
+	 */
+	ring = engine->context_pin(engine, shadow_ctx);
+	if (IS_ERR(ring)) {
+		ret = PTR_ERR(ring);
+		gvt_vgpu_err("fail to pin shadow context\n");
+		goto out;
+	}
 
-	ret = 0;
-	workload->dispatched = true;
 out:
 	if (ret)
 		workload->status = ret;
 
-	if (!IS_ERR_OR_NULL(rq))
-		i915_add_request(rq);
-	else
-		engine->context_unpin(engine, shadow_ctx);
+	if (!IS_ERR_OR_NULL(workload->req)) {
+		gvt_dbg_sched("ring id %d submit workload to i915 %p\n",
+				ring_id, workload->req);
+		i915_add_request(workload->req);
+		workload->dispatched = true;
+	}
 
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 	return ret;
@@ -630,5 +677,7 @@ int intel_vgpu_init_gvt_context(struct intel_vgpu *vgpu)
 
 	vgpu->shadow_ctx->engine[RCS].initialised = true;
 
+	bitmap_zero(vgpu->shadow_ctx_desc_updated, I915_NUM_ENGINES);
+
 	return 0;
 }
diff --git a/drivers/gpu/drm/i915/gvt/scheduler.h b/drivers/gpu/drm/i915/gvt/scheduler.h
index 9b6bf51e9b9b..0d431a968a32 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.h
+++ b/drivers/gpu/drm/i915/gvt/scheduler.h
@@ -82,6 +82,7 @@ struct intel_vgpu_workload {
 	struct drm_i915_gem_request *req;
 	/* if this workload has been dispatched to i915? */
 	bool dispatched;
+	bool shadowed;
 	int status;
 
 	struct intel_vgpu_mm *shadow_mm;
diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index 90c14e6e3ea0..5896ead8529e 100644
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -43,6 +43,7 @@ void populate_pvinfo_page(struct intel_vgpu *vgpu)
 	vgpu_vreg(vgpu, vgtif_reg(version_minor)) = 0;
 	vgpu_vreg(vgpu, vgtif_reg(display_ready)) = 0;
 	vgpu_vreg(vgpu, vgtif_reg(vgt_id)) = vgpu->id;
+	vgpu_vreg(vgpu, vgtif_reg(vgt_caps)) = VGT_CAPS_FULL_48BIT_PPGTT;
 	vgpu_vreg(vgpu, vgtif_reg(avail_rs.mappable_gmadr.base)) =
 		vgpu_aperture_gmadr_base(vgpu);
 	vgpu_vreg(vgpu, vgtif_reg(avail_rs.mappable_gmadr.size)) =
@@ -502,11 +503,11 @@ void intel_gvt_reset_vgpu_locked(struct intel_vgpu *vgpu, bool dmlr,
 	/* full GPU reset or device model level reset */
 	if (engine_mask == ALL_ENGINES || dmlr) {
 
-		intel_vgpu_reset_gtt(vgpu, dmlr);
-
 		/*fence will not be reset during virtual reset */
-		if (dmlr)
+		if (dmlr) {
+			intel_vgpu_reset_gtt(vgpu);
 			intel_vgpu_reset_resource(vgpu);
+		}
 
 		intel_vgpu_reset_mmio(vgpu, dmlr);
 		populate_pvinfo_page(vgpu);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ef5af697732d..5aa214a05c51 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1905,6 +1905,7 @@ struct i915_workarounds {
 
 struct i915_virtual_gpu {
 	bool active;
+	u32 caps;
 };
 
 /* used in computing the new watermarks state */
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 10aa7762d9a6..ef1881e256f4 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -144,9 +144,9 @@ int intel_sanitize_enable_ppgtt(struct drm_i915_private *dev_priv,
 	has_full_48bit_ppgtt = dev_priv->info.has_full_48bit_ppgtt;
 
 	if (intel_vgpu_active(dev_priv)) {
-		/* emulation is too hard */
+		/* GVT-g has no support for 32bit ppgtt */
 		has_full_ppgtt = false;
-		has_full_48bit_ppgtt = false;
+		has_full_48bit_ppgtt = intel_vgpu_has_full_48bit_ppgtt(dev_priv);
 	}
 
 	if (!has_aliasing_ppgtt)
@@ -180,10 +180,15 @@ int intel_sanitize_enable_ppgtt(struct drm_i915_private *dev_priv,
 		return 0;
 	}
 
-	if (INTEL_GEN(dev_priv) >= 8 && i915.enable_execlists && has_full_ppgtt)
-		return has_full_48bit_ppgtt ? 3 : 2;
-	else
-		return has_aliasing_ppgtt ? 1 : 0;
+	if (INTEL_GEN(dev_priv) >= 8 && i915.enable_execlists) {
+		if (has_full_48bit_ppgtt)
+			return 3;
+
+		if (has_full_ppgtt)
+			return 2;
+	}
+
+	return has_aliasing_ppgtt ? 1 : 0;
 }
 
 static int ppgtt_bind_vma(struct i915_vma *vma,
diff --git a/drivers/gpu/drm/i915/i915_pvinfo.h b/drivers/gpu/drm/i915/i915_pvinfo.h
index 2cfe96d3e5d1..0679a58cdbae 100644
--- a/drivers/gpu/drm/i915/i915_pvinfo.h
+++ b/drivers/gpu/drm/i915/i915_pvinfo.h
@@ -49,12 +49,18 @@ enum vgt_g2v_type {
 	VGT_G2V_MAX,
 };
 
+/*
+ * VGT capabilities type
+ */
+#define VGT_CAPS_FULL_48BIT_PPGTT	BIT(2)
+
 struct vgt_if {
 	u64 magic;		/* VGT_MAGIC */
 	u16 version_major;
 	u16 version_minor;
 	u32 vgt_id;		/* ID of vGT instance */
-	u32 rsv1[12];		/* pad to offset 0x40 */
+	u32 vgt_caps;		/* VGT capabilities */
+	u32 rsv1[11];		/* pad to offset 0x40 */
 	/*
 	 *  Data structure to describe the balooning info of resources.
 	 *  Each VM can only have one portion of continuous area for now.
diff --git a/drivers/gpu/drm/i915/i915_vgpu.c b/drivers/gpu/drm/i915/i915_vgpu.c
index cf7a958e4d3c..5fe9f3f39467 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.c
+++ b/drivers/gpu/drm/i915/i915_vgpu.c
@@ -75,10 +75,17 @@ void i915_check_vgpu(struct drm_i915_private *dev_priv)
 		return;
 	}
 
+	dev_priv->vgpu.caps = __raw_i915_read32(dev_priv, vgtif_reg(vgt_caps));
+
 	dev_priv->vgpu.active = true;
 	DRM_INFO("Virtual GPU for Intel GVT-g detected.\n");
 }
 
+bool intel_vgpu_has_full_48bit_ppgtt(struct drm_i915_private *dev_priv)
+{
+	return dev_priv->vgpu.caps & VGT_CAPS_FULL_48BIT_PPGTT;
+}
+
 struct _balloon_info_ {
 	/*
 	 * There are up to 2 regions per mappable/unmappable graphic
diff --git a/drivers/gpu/drm/i915/i915_vgpu.h b/drivers/gpu/drm/i915/i915_vgpu.h
index 3c3b2d24e830..b72bd2956b70 100644
--- a/drivers/gpu/drm/i915/i915_vgpu.h
+++ b/drivers/gpu/drm/i915/i915_vgpu.h
@@ -27,6 +27,9 @@
 #include "i915_pvinfo.h"
 
 void i915_check_vgpu(struct drm_i915_private *dev_priv);
+
+bool intel_vgpu_has_full_48bit_ppgtt(struct drm_i915_private *dev_priv);
+
 int intel_vgt_balloon(struct drm_i915_private *dev_priv);
 void intel_vgt_deballoon(struct drm_i915_private *dev_priv);