3 files changed, 49 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index f6f2ab2683f7..dffd4b79b9a6 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -2337,12 +2337,27 @@ int intel_vgpu_emulate_ggtt_mmio_write(struct intel_vgpu *vgpu,
 {
 	const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
 	int ret;
+	struct intel_vgpu_submission *s = &vgpu->submission;
+	struct intel_engine_cs *engine;
+	int i;
 
 	if (bytes != 4 && bytes != 8)
 		return -EINVAL;
 
 	off -= info->gtt_start_offset;
 	ret = emulate_ggtt_mmio_write(vgpu, off, p_data, bytes);
+
+	/* if ggtt of last submitted context is written,
+	 * that context is probably got unpinned.
+	 * Set last shadowed ctx to invalid.
+	 */
+	for_each_engine(engine, vgpu->gvt->gt, i) {
+		if (!s->last_ctx[i].valid)
+			continue;
+
+		if (s->last_ctx[i].lrca == (off >> info->gtt_entry_size_shift))
+			s->last_ctx[i].valid = false;
+	}
 	return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index 58c2c7932e3f..a4a6db6b7f90 100644
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -163,6 +163,11 @@ struct intel_vgpu_submission {
 	const struct intel_vgpu_submission_ops *ops;
 	int virtual_submission_interface;
 	bool active;
+	struct {
+		u32 lrca;
+		bool valid;
+		u64 ring_context_gpa;
+	} last_ctx[I915_NUM_ENGINES];
 };
 
 struct intel_vgpu {
diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c
index f650ad3367b6..92a055c9d8d8 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -135,7 +135,10 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 	unsigned long context_gpa, context_page_num;
 	unsigned long gpa_base; /* first gpa of consecutive GPAs */
 	unsigned long gpa_size; /* size of consecutive GPAs */
+	struct intel_vgpu_submission *s = &vgpu->submission;
 	int i;
+	bool skip = false;
+	int ring_id = workload->engine->id;
 
 	GEM_BUG_ON(!intel_context_is_pinned(ctx));
 
@@ -175,13 +178,31 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 
 	sr_oa_regs(workload, (u32 *)shadow_ring_context, false);
 
-	if (IS_RESTORE_INHIBIT(shadow_ring_context->ctx_ctrl.val))
-		return 0;
+	gvt_dbg_sched("ring %s workload lrca %x, ctx_id %x, ctx gpa %llx",
+			workload->engine->name, workload->ctx_desc.lrca,
+			workload->ctx_desc.context_id,
+			workload->ring_context_gpa);
 
-	gvt_dbg_sched("ring %s workload lrca %x",
-		      workload->engine->name,
-		      workload->ctx_desc.lrca);
+	/* only need to ensure this context is not pinned/unpinned during the
+	 * period from last submission to this this submission.
+	 * Upon reaching this function, the currently submitted context is not
+	 * supposed to get unpinned. If a misbehaving guest driver ever does
+	 * this, it would corrupt itself.
+	 */
+	if (s->last_ctx[ring_id].valid &&
+			(s->last_ctx[ring_id].lrca ==
+				workload->ctx_desc.lrca) &&
+			(s->last_ctx[ring_id].ring_context_gpa ==
+				workload->ring_context_gpa))
+		skip = true;
 
+	s->last_ctx[ring_id].lrca = workload->ctx_desc.lrca;
+	s->last_ctx[ring_id].ring_context_gpa = workload->ring_context_gpa;
+
+	if (IS_RESTORE_INHIBIT(shadow_ring_context->ctx_ctrl.val) || skip)
+		return 0;
+
+	s->last_ctx[ring_id].valid = false;
 	context_page_num = workload->engine->context_size;
 	context_page_num = context_page_num >> PAGE_SHIFT;
 
@@ -220,6 +241,7 @@ read:
 		gpa_size = I915_GTT_PAGE_SIZE;
 		dst = context_base + (i << I915_GTT_PAGE_SHIFT);
 	}
+	s->last_ctx[ring_id].valid = true;
 	return 0;
 }
 
@@ -1296,6 +1318,8 @@ int intel_vgpu_setup_submission(struct intel_vgpu *vgpu)
 	atomic_set(&s->running_workload_num, 0);
 	bitmap_zero(s->tlb_handle_pending, I915_NUM_ENGINES);
 
+	memset(s->last_ctx, 0, sizeof(s->last_ctx));
+
 	i915_vm_put(&ppgtt->vm);
 	return 0;