The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6e3f17ee73f7e3c2ef0e2c8fd8624b2ece8ef2c9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= noralf@tronnes.org Date: Mon, 1 Apr 2019 16:13:58 +0200 Subject: [PATCH] drm/fb-helper: generic: Call drm_client_add() after setup is done MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
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@vger.kernel.org Reported-by: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Noralf Trønnes noralf@tronnes.org Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch Link: https://patchwork.freedesktop.org/patch/msgid/20190401141358.25309-1-noralf@...
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 0d8384e30e16..84791dd4a90d 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -3312,8 +3312,6 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) return ret; }
- drm_client_add(&fb_helper->client); - if (!preferred_bpp) preferred_bpp = dev->mode_config.preferred_depth; if (!preferred_bpp) @@ -3324,6 +3322,8 @@ int drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) 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);