Your proprietary module is still loaded. You need to remove it completely from the system so that it doesn't load automatically. [ 1.946359] wl: loading out-of-tree module taints kernel. [ 1.946366] wl: module license 'MIXED/Proprietary' taints kernel. [ 1.946368] Disabling lock debugging due to kernel taint [ 1.948274] wl: module verification failed: signature and/or required key missing - tainting kernel