Gerd Hoffmann
2019-Mar-11 06:22 UTC
[PATCH] drm/bochs: Fix NULL dereference on atomic_disable helper
On Sun, Mar 10, 2019 at 06:21:50PM -0300, Rodrigo Siqueira wrote:> When the subtest basic-plain-flip from IGT project was executed on Bochs > driver, the following bug appears: > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000> ? drm_atomic_helper_commit_modeset_disables+0x396/0x3e0 [drm_kms_helper]> +static void bochs_crtc_atomic_disable(struct drm_crtc *crtc, > + struct drm_crtc_state *old_state) > +{ > +} > + > static void bochs_crtc_atomic_flush(struct drm_crtc *crtc, > struct drm_crtc_state *old_crtc_state) > { > @@ -66,6 +71,7 @@ static const struct drm_crtc_funcs bochs_crtc_funcs = { > static const struct drm_crtc_helper_funcs bochs_helper_funcs = { > .mode_set_nofb = bochs_crtc_mode_set_nofb, > .atomic_enable = bochs_crtc_atomic_enable, > + .atomic_disable = bochs_crtc_atomic_disable,Shouldn't we make the callback optional instead of adding empty dummy functions to drivers? cheers, Gerd