When this config is not set the drm module will miss symbols and not load. [ 3.199840] nvidia-modeset: Loading NVIDIA Kernel Mode Setting Driver for UNIX platforms 364.12 Wed Mar 16 20:44:12 PDT 2016 [ 3.208952] nvidia_drm: Unknown symbol drm_atomic_helper_plane_destroy_state (err 0) [ 3.209008] nvidia_drm: Unknown symbol drm_kms_helper_poll_fini (err 0) [ 3.209049] nvidia_drm: Unknown symbol drm_kms_helper_poll_disable (err 0) [ 3.209089] nvidia_drm: Unknown symbol drm_kms_helper_poll_init (err 0) [ 3.209131] nvidia_drm: Unknown symbol drm_atomic_helper_disable_plane (err 0) [ 3.209184] nvidia_drm: Unknown symbol drm_atomic_helper_cleanup_planes (err 0) [ 3.209238] nvidia_drm: Unknown symbol drm_helper_hpd_irq_event (err 0) [ 3.211937] nvidia_drm: Unknown symbol drm_atomic_helper_crtc_destroy_state (err 0) [ 3.211993] nvidia_drm: Unknown symbol drm_atomic_helper_connector_dpms (err 0) [ 3.212048] nvidia_drm: Unknown symbol drm_atomic_helper_check (err 0) [ 3.212088] nvidia_drm: Unknown symbol drm_atomic_helper_connector_destroy_state (err 0) [ 3.212143] nvidia_drm: Unknown symbol drm_atomic_helper_plane_duplicate_state (err 0) [ 3.212204] nvidia_drm: Unknown symbol drm_atomic_helper_plane_reset (err 0) [ 3.212244] nvidia_drm: Unknown symbol drm_atomic_helper_prepare_planes (err 0) [ 3.212300] nvidia_drm: Unknown symbol drm_helper_mode_fill_fb_struct (err 0) [ 3.212344] nvidia_drm: Unknown symbol drm_atomic_helper_set_config (err 0) [ 3.212384] nvidia_drm: Unknown symbol drm_atomic_helper_connector_duplicate_state (err 0) [ 3.212439] nvidia_drm: Unknown symbol drm_atomic_helper_crtc_reset (err 0) [ 3.212483] nvidia_drm: Unknown symbol drm_kms_helper_hotplug_event (err 0) [ 3.212525] nvidia_drm: Unknown symbol drm_atomic_helper_swap_state (err 0) [ 3.212566] nvidia_drm: Unknown symbol drm_atomic_helper_page_flip (err 0) [ 3.212606] nvidia_drm: Unknown symbol drm_atomic_helper_connector_reset (err 0) [ 3.212660] nvidia_drm: Unknown symbol drm_atomic_helper_crtc_duplicate_state (err 0) [ 3.212714] nvidia_drm: Unknown symbol drm_atomic_helper_update_plane (err 0)
*** Bug 578830 has been marked as a duplicate of this bug. ***
I can confirm that CONFIG_DRM_FBDEV_EMULATION, FB_MODE_HELPERS are needed.
Only CONFIG_DRM_FBDEV_EMULATION is neccesary for building and loading the drm module. However CONFIG_FB_MODE_HELPERS did not help my situation of xcom2 saying my gfx card is not support and low fps in ns2.
I found the FBDEV thing last week, but I do not have FB_MODE_HELPERS in my kernel and haven't had a single issue or error with the drivers
I believe this may have been only relevant when using modeset=1 Either way, addition of DRM and DRM_KMS_HELPER would ensure everything is available: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=b69bae801a904d7f31145bfba5a50f11a9cbbdf7 DRM_KMS_HELPER notably pulls DRM_FBDEV_EMULATION, so I'll mark this fixed.
However, the DRM_KMS_HELPER config option being not directly available is another issue, bug #603818 is still open about this.
