4 files changed, 43 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 7db7b37937e7..1f0b5c37f6de 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -416,6 +416,15 @@ struct drm_i915_file_private {
 	} rps;
 
 	unsigned int bsd_engine;
+
+/* Client can have a maximum of 3 contexts banned before
+ * it is denied of creating new contexts. As one context
+ * ban needs 4 consecutive hangs, and more if there is
+ * progress in between, this is a last resort stop gap measure
+ * to limit the badly behaving clients access to gpu.
+ */
+#define I915_MAX_CLIENT_CONTEXT_BANS 3
+	int context_bans;
 };
 
 /* Used by dp and fdi links */
@@ -872,6 +881,7 @@ struct drm_i915_error_state {
 
 		pid_t pid;
 		char comm[TASK_COMM_LEN];
+		int context_bans;
 	} engine[I915_NUM_ENGINES];
 
 	struct drm_i915_error_buffer {
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 99198146ecc8..a8118386a23b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2646,6 +2646,20 @@ static void i915_gem_context_mark_guilty(struct i915_gem_context *ctx)
 
 	hs->banned = i915_context_is_banned(ctx);
 	hs->batch_active++;
+
+	DRM_DEBUG_DRIVER("context %s marked guilty (score %d) banned? %s\n",
+			 ctx->name, hs->ban_score, yesno(hs->banned));
+
+	if (!ctx->file_priv)
+		return;
+
+	if (hs->banned) {
+		ctx->file_priv->context_bans++;
+
+		DRM_DEBUG_DRIVER("client %s has has %d context banned\n",
+				 ctx->name,
+				 ctx->file_priv->context_bans);
+	}
 }
 
 static void i915_gem_context_mark_innocent(struct i915_gem_context *ctx)
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 97012373a8d5..88d59866c433 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -1003,6 +1003,11 @@ static bool contexts_enabled(struct drm_device *dev)
 	return i915.enable_execlists || to_i915(dev)->hw_context_size;
 }
 
+static bool client_is_banned(struct drm_i915_file_private *file_priv)
+{
+	return file_priv->context_bans > I915_MAX_CLIENT_CONTEXT_BANS;
+}
+
 int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
 				  struct drm_file *file)
 {
@@ -1017,6 +1022,14 @@ int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
 	if (args->pad != 0)
 		return -EINVAL;
 
+	if (client_is_banned(file_priv)) {
+		DRM_DEBUG("client %s[%d] banned from creating ctx\n",
+			  current->comm,
+			  pid_nr(get_task_pid(current, PIDTYPE_PID)));
+
+		return -EIO;
+	}
+
 	ret = i915_mutex_lock_interruptible(dev);
 	if (ret)
 		return ret;
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index fa988a00ae68..af4f0ef4fa08 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -538,10 +538,11 @@ int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 	for (i = 0; i < ARRAY_SIZE(error->engine); i++) {
 		if (error->engine[i].hangcheck_stalled &&
 		    error->engine[i].pid != -1) {
-			err_printf(m, "Active process (on ring %s): %s [%d]\n",
+			err_printf(m, "Active process (on ring %s): %s [%d], context bans %d\n",
 				   engine_str(i),
 				   error->engine[i].comm,
-				   error->engine[i].pid);
+				   error->engine[i].pid,
+				   error->engine[i].context_bans);
 		}
 	}
 	err_printf(m, "Reset count: %u\n", error->reset_count);
@@ -632,9 +633,10 @@ int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 		if (obj) {
 			err_puts(m, dev_priv->engine[i]->name);
 			if (ee->pid != -1)
-				err_printf(m, " (submitted by %s [%d])",
+				err_printf(m, " (submitted by %s [%d], bans %d)",
 					   ee->comm,
-					   ee->pid);
+					   ee->pid,
+					   ee->context_bans);
 			err_printf(m, " --- gtt_offset = 0x%08x %08x\n",
 				   upper_32_bits(obj->gtt_offset),
 				   lower_32_bits(obj->gtt_offset));