Am Mittwoch, 15. März 2017, 18:00:04 CET schrieb Heiko Stuebner:
Am Mittwoch, 15. März 2017, 18:20:47 CET schrieb Jeffy Chen:
Currently we are adding all components from the dts, if one of their drivers been disabled, we would not be able to bring up others.
Refactor component match logic, follow exynos drm.
Signed-off-by: Jeffy Chen jeffy.chen@rock-chips.com Reviewed-by: Andrzej Hajda a.hajda@samsung.com
This reliably produces null pointer dereference errors in __platform_driver_register called from rockchip_drm_init on at least rk3036 and rk3288 (probably more) when applied on top of Linus' tree from today. Log attached and Rockchip drm compiled as module.
I'm currently dug into other areas, so hadn't have time to investigate further yet.
+#define DRV_PTR(drv, cond) (IS_ENABLED(cond) ? &drv : NULL)
+static struct platform_driver *rockchip_drm_comp_drvs[] = {
- &vop_platform_driver,
- DRV_PTR(rockchip_dp_driver, CONFIG_ROCKCHIP_ANALOGIX_DP),
- DRV_PTR(cdn_dp_driver, CONFIG_ROCKCHIP_CDN_DP),
- DRV_PTR(dw_hdmi_rockchip_pltfm_driver, CONFIG_ROCKCHIP_DW_HDMI),
- DRV_PTR(dw_mipi_dsi_driver, CONFIG_ROCKCHIP_DW_MIPI_DSI),
- DRV_PTR(inno_hdmi_driver, CONFIG_ROCKCHIP_INNO_HDMI),
+};
[...]
+static int rockchip_drm_register_drivers(void) +{
- int i, ret;
- for (i = 0; i < ARRAY_SIZE(rockchip_drm_comp_drvs); i++) {
ret = platform_driver_register(rockchip_drm_comp_drvs[i]);if (ret)goto err_unreg;- }
This of course won't work in the NULL case, as platform_driver_register always dereferences its parameter [0], so you should only call it for the actual non- null array elements - of course same for unregister.
Heiko
[0] http://lxr.free-electrons.com/source/drivers/base/platform.c#L617