drm/connector: notify userspace on hotplug after register complete

commit 968d81a64a883af2d16dd3f8a6ad6b67db2fde58 upstream.

drm connector notifies userspace on hotplug event prematurely before
late_register and mode_object register completes. This leads to a race
between userspace and kernel on updating the IDR list. So, move the
notification to end of connector register.

Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Steve Cohen <cohens@codeaurora.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1591155451-10393-1-git-send-email-jsanka@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 4c766624b20d31e8b827313b887728cc797c8051..2337b3827e6a4dd47a61c4df235e50c345b52827 100644 (file)
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -27,6 +27,7 @@
 #include <drm/drm_print.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
+#include <drm/drm_sysfs.h>
 
 #include <linux/uaccess.h>
 
@@ -511,6 +512,10 @@ int drm_connector_register(struct drm_connector *connector)
        drm_mode_object_register(connector->dev, &connector->base);
 
        connector->registration_state = DRM_CONNECTOR_REGISTERED;
+
+       /* Let userspace know we have a new connector */
+       drm_sysfs_hotplug_event(connector->dev);
+
        goto unlock;
 
 err_debugfs:

diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index dd2bc85f43cc8efa07f8b5aec62a76581ca59ee9..4fd2f6cd03c148676a8b8e839828a5382483042b 100644 (file)
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -293,9 +293,6 @@ int drm_sysfs_connector_add(struct drm_connector *connector)
                return PTR_ERR(connector->kdev);
        }
 
-       /* Let userspace know we have a new connector */
-       drm_sysfs_hotplug_event(dev);
-
        if (connector->ddc)
                return sysfs_create_link(&connector->kdev->kobj,
                                 &connector->ddc->dev.kobj, "ddc");