From 657a091ab6d01d0091b77660c75cfed573c9a53e Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 8 May 2026 16:44:45 +0200 Subject: [PATCH] drm/gma500/oaktrail_lvds: fix hang on init failure The LVDS init code looks up an I2C adapter using i2c_get_adapter() and tries to read the EDID before falling back to allocating and registering its own adapter. The error handling does not separate these cases so on a late init failure it will try to deregister and free also an adapter that had previously been registered. Since i2c_get_adapter() takes another reference to the adapter, deregistration hangs indefinitely while waiting for the reference to be released. Fix this by only destroying adapters allocated during LVDS init on errors. Fixes: a57ebfc0b4da ("drm/gma500: Make oaktrail lvds use ddc adapter from drm_connector") Cc: stable@vger.kernel.org # 6.0 Cc: Patrik Jakobsson Signed-off-by: Johan Hovold Signed-off-by: Patrik Jakobsson Link: https://patch.msgid.link/20260508144446.59722-3-johan@kernel.org --- drivers/gpu/drm/gma500/oaktrail_lvds.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds.c b/drivers/gpu/drm/gma500/oaktrail_lvds.c index 884d324f0044..983cc60a1e69 100644 --- a/drivers/gpu/drm/gma500/oaktrail_lvds.c +++ b/drivers/gpu/drm/gma500/oaktrail_lvds.c @@ -293,7 +293,7 @@ void oaktrail_lvds_init(struct drm_device *dev, { struct gma_encoder *gma_encoder; struct gma_connector *gma_connector; - struct gma_i2c_chan *ddc_bus; + struct gma_i2c_chan *ddc_bus = NULL; struct drm_connector *connector; struct drm_encoder *encoder; struct drm_psb_private *dev_priv = to_drm_psb_private(dev); @@ -421,7 +421,8 @@ void oaktrail_lvds_init(struct drm_device *dev, err_unlock: mutex_unlock(&dev->mode_config.mutex); - gma_i2c_destroy(to_gma_i2c_chan(connector->ddc)); + if (!IS_ERR_OR_NULL(ddc_bus)) + gma_i2c_destroy(ddc_bus); drm_encoder_cleanup(encoder); err_connector_cleanup: drm_connector_cleanup(connector);