Messages in this thread | | | Date | Fri, 23 Nov 2018 09:33:10 -0800 | From | Tony Lindgren <> | Subject | Re: [PATCHv5 4/6] drm/omap: fix incorrect union usage |
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* Sebastian Reichel <sebastian.reichel@collabora.com> [181121 16:09]: > The DSI encoder sets dssdev->ops->dsi.set_config, which is stored at the > same offset as dssdev->ops->hdmi.set_hdmi_mode. The code in omap_encoder > only checks if dssdev->ops->hdmi.set_hdmi_mode is NULL. Due to the way > union works, it won't be NULL if dsi.set_config is set. This means > dsi_set_config will be called with config=hdmi_mode=false=NULL parameter > resulting in a NULL dereference. Also the dereference happens while > console is locked, so kernel hangs without any debug output without > "fb.lockless_register_fb=1" parameter. > > This restructures the code, so that the HDMI mode is only configured > for HDMI output types. The new function also has a safe-guard directly > before accessing the union, that can be optimized away by the compiler > when the function is inlined and HDMI type has already been checked. > > Fixes: 83910ad3f51fb ("drm/omap: Move most omap_dss_driver operations to omap_dss_device_ops") > Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Works for me:
Tested-by: Tony Lindgren <tony@atomide.com>
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