From: Jeykumar Sankaran jsanka@codeaurora.org
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-em... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/drm_connector.c | 5 +++++ drivers/gpu/drm/drm_sysfs.c | 3 --- 2 files changed, 5 insertions(+), 3 deletions(-)
--- 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>
@@ -523,6 +524,10 @@ int drm_connector_register(struct drm_co 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: --- a/drivers/gpu/drm/drm_sysfs.c +++ b/drivers/gpu/drm/drm_sysfs.c @@ -291,9 +291,6 @@ int drm_sysfs_connector_add(struct drm_c 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");