4 files changed, 53 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index a529d2bd393c..8d5317d0122d 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -997,9 +997,11 @@ static inline void ppgtt_generate_shadow_entry(struct intel_gvt_gtt_entry *se,
 static int ppgtt_populate_shadow_page(struct intel_vgpu_ppgtt_spt *spt)
 {
 	struct intel_vgpu *vgpu = spt->vgpu;
+	struct intel_gvt *gvt = vgpu->gvt;
+	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
 	struct intel_vgpu_ppgtt_spt *s;
 	struct intel_gvt_gtt_entry se, ge;
-	unsigned long i;
+	unsigned long gfn, i;
 	int ret;
 
 	trace_spt_change(spt->vgpu->id, "born", spt,
@@ -1007,9 +1009,10 @@ static int ppgtt_populate_shadow_page(struct intel_vgpu_ppgtt_spt *spt)
 
 	if (gtt_type_is_pte_pt(spt->shadow_page.type)) {
 		for_each_present_guest_entry(spt, &ge, i) {
-			ret = gtt_entry_p2m(vgpu, &ge, &se);
-			if (ret)
-				goto fail;
+			gfn = ops->get_pfn(&ge);
+			if (!intel_gvt_hypervisor_is_valid_gfn(vgpu, gfn) ||
+				gtt_entry_p2m(vgpu, &ge, &se))
+				ops->set_pfn(&se, gvt->gtt.scratch_mfn);
 			ppgtt_set_shadow_entry(spt, &se, i);
 		}
 		return 0;
@@ -1906,7 +1909,7 @@ static int emulate_gtt_mmio_write(struct intel_vgpu *vgpu, unsigned int off,
 	struct intel_vgpu_mm *ggtt_mm = vgpu->gtt.ggtt_mm;
 	struct intel_gvt_gtt_pte_ops *ops = gvt->gtt.pte_ops;
 	unsigned long g_gtt_index = off >> info->gtt_entry_size_shift;
-	unsigned long gma;
+	unsigned long gma, gfn;
 	struct intel_gvt_gtt_entry e, m;
 	int ret;
 
@@ -1925,6 +1928,16 @@ static int emulate_gtt_mmio_write(struct intel_vgpu *vgpu, unsigned int off,
 			bytes);
 
 	if (ops->test_present(&e)) {
+		gfn = ops->get_pfn(&e);
+
+		/* one PTE update may be issued in multiple writes and the
+		 * first write may not construct a valid gfn
+		 */
+		if (!intel_gvt_hypervisor_is_valid_gfn(vgpu, gfn)) {
+			ops->set_pfn(&m, gvt->gtt.scratch_mfn);
+			goto out;
+		}
+
 		ret = gtt_entry_p2m(vgpu, &e, &m);
 		if (ret) {
 			gvt_vgpu_err("fail to translate guest gtt entry\n");
@@ -1939,6 +1952,7 @@ static int emulate_gtt_mmio_write(struct intel_vgpu *vgpu, unsigned int off,
 		ops->set_pfn(&m, gvt->gtt.scratch_mfn);
 	}
 
+out:
 	ggtt_set_shadow_entry(ggtt_mm, &m, g_gtt_index);
 	gtt_invalidate(gvt->dev_priv);
 	ggtt_set_guest_entry(ggtt_mm, &e, g_gtt_index);
diff --git a/drivers/gpu/drm/i915/gvt/hypercall.h b/drivers/gpu/drm/i915/gvt/hypercall.h
index a1bd82feb827..f8e77e166246 100644
--- a/drivers/gpu/drm/i915/gvt/hypercall.h
+++ b/drivers/gpu/drm/i915/gvt/hypercall.h
@@ -58,6 +58,7 @@ struct intel_gvt_mpt {
 	int (*set_opregion)(void *vgpu);
 	int (*get_vfio_device)(void *vgpu);
 	void (*put_vfio_device)(void *vgpu);
+	bool (*is_valid_gfn)(unsigned long handle, unsigned long gfn);
 };
 
 extern struct intel_gvt_mpt xengt_mpt;
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 45bab5a6290b..eb92572056c3 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1570,6 +1570,21 @@ static unsigned long kvmgt_virt_to_pfn(void *addr)
 	return PFN_DOWN(__pa(addr));
 }
 
+static bool kvmgt_is_valid_gfn(unsigned long handle, unsigned long gfn)
+{
+	struct kvmgt_guest_info *info;
+	struct kvm *kvm;
+
+	if (!handle_valid(handle))
+		return false;
+
+	info = (struct kvmgt_guest_info *)handle;
+	kvm = info->kvm;
+
+	return kvm_is_visible_gfn(kvm, gfn);
+
+}
+
 struct intel_gvt_mpt kvmgt_mpt = {
 	.host_init = kvmgt_host_init,
 	.host_exit = kvmgt_host_exit,
@@ -1585,6 +1600,7 @@ struct intel_gvt_mpt kvmgt_mpt = {
 	.set_opregion = kvmgt_set_opregion,
 	.get_vfio_device = kvmgt_get_vfio_device,
 	.put_vfio_device = kvmgt_put_vfio_device,
+	.is_valid_gfn = kvmgt_is_valid_gfn,
 };
 EXPORT_SYMBOL_GPL(kvmgt_mpt);
 
diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h
index ca8005a6d5fa..81aff4eacbfe 100644
--- a/drivers/gpu/drm/i915/gvt/mpt.h
+++ b/drivers/gpu/drm/i915/gvt/mpt.h
@@ -339,4 +339,21 @@ static inline void intel_gvt_hypervisor_put_vfio_device(struct intel_vgpu *vgpu)
 	intel_gvt_host.mpt->put_vfio_device(vgpu);
 }
 
+/**
+ * intel_gvt_hypervisor_is_valid_gfn - check if a visible gfn
+ * @vgpu: a vGPU
+ * @gfn: guest PFN
+ *
+ * Returns:
+ * true on valid gfn, false on not.
+ */
+static inline bool intel_gvt_hypervisor_is_valid_gfn(
+		struct intel_vgpu *vgpu, unsigned long gfn)
+{
+	if (!intel_gvt_host.mpt->is_valid_gfn)
+		return true;
+
+	return intel_gvt_host.mpt->is_valid_gfn(vgpu->handle, gfn);
+}
+
 #endif /* _GVT_MPT_H_ */