From 4813766325374af6ed0b66879ba6a0bbb05c83b6 Mon Sep 17 00:00:00 2001
From: Pavel Roskin <plroskin@gmail.com>
Date: Sat, 23 Sep 2017 13:10:33 -0700
Subject: [PATCH] drm/nouveau/fbcon: fix oops without fbdev emulation
Git-commit: 4813766325374af6ed0b66879ba6a0bbb05c83b6
Patch-mainline: v4.14-rc6
References: bsc#1094751

This is similar to an earlier commit 52dfcc5ccfbb ("drm/nouveau: fix for
disabled fbdev emulation"), but protects all occurrences of helper.fbdev
in the source.

I see oops in nouveau_fbcon_accel_save_disable() called from
nouveau_fbcon_set_suspend_work() on Linux 3.13 when
CONFIG_DRM_FBDEV_EMULATION option is disabled.

Signed-off-by: Pavel Roskin <plroskin@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/nouveau/nouveau_fbcon.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -223,7 +223,7 @@ void
 nouveau_fbcon_accel_save_disable(struct drm_device *dev)
 {
 	struct nouveau_drm *drm = nouveau_drm(dev);
-	if (drm->fbcon) {
+	if (drm->fbcon && drm->fbcon->helper.fbdev) {
 		drm->fbcon->saved_flags = drm->fbcon->helper.fbdev->flags;
 		drm->fbcon->helper.fbdev->flags |= FBINFO_HWACCEL_DISABLED;
 	}
@@ -233,7 +233,7 @@ void
 nouveau_fbcon_accel_restore(struct drm_device *dev)
 {
 	struct nouveau_drm *drm = nouveau_drm(dev);
-	if (drm->fbcon) {
+	if (drm->fbcon && drm->fbcon->helper.fbdev) {
 		drm->fbcon->helper.fbdev->flags = drm->fbcon->saved_flags;
 	}
 }
@@ -245,7 +245,8 @@ nouveau_fbcon_accel_fini(struct drm_devi
 	struct nouveau_fbdev *fbcon = drm->fbcon;
 	if (fbcon && drm->channel) {
 		console_lock();
-		fbcon->helper.fbdev->flags |= FBINFO_HWACCEL_DISABLED;
+		if (fbcon->helper.fbdev)
+			fbcon->helper.fbdev->flags |= FBINFO_HWACCEL_DISABLED;
 		console_unlock();
 		nouveau_channel_idle(drm->channel);
 		nvif_object_fini(&fbcon->twod);