[PATCH 5.1 78/85] drm/fb-helper: generic: Call drm_client_add() after setup is done

[Greg Kroah-Hartman]

From: Noralf TrÃnnes <noralf@xxxxxxxxxxx>

commit 6e3f17ee73f7e3c2ef0e2c8fd8624b2ece8ef2c9 upstream.

Hotplug can happen while drm_fbdev_generic_setup() is running so move
drm_client_add() call after setup is done to avoid
drm_fbdev_client_hotplug() running in two threads at the same time.

Fixes: 9060d7f49376 ("drm/fb-helper: Finish the generic fbdev emulation")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Signed-off-by: Noralf TrÃnnes <noralf@xxxxxxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401141358.25309-1-noralf@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/drm_fb_helper.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -3317,8 +3317,6 @@ int drm_fbdev_generic_setup(struct drm_d
 		return ret;
 	}
 
-	drm_client_add(&fb_helper->client);
-
 	if (!preferred_bpp)
 		preferred_bpp = dev->mode_config.preferred_depth;
 	if (!preferred_bpp)
@@ -3329,6 +3327,8 @@ int drm_fbdev_generic_setup(struct drm_d
 	if (ret)
 		DRM_DEV_DEBUG(dev->dev, "client hotplug ret=%d\n", ret);
 
+	drm_client_add(&fb_helper->client);
+
 	return 0;
 }
 EXPORT_SYMBOL(drm_fbdev_generic_setup);