Op 12-07-15 om 18:52 schreef Linus Torvalds:
On Sun, Jul 12, 2015 at 1:03 AM, Jörg Otte jrg.otte@gmail.com wrote:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000009 IP: [<ffffffffbd3447bb>] 0xffffffffbd3447bb
Ugh. Please enable KALLSYMS to get sane symbols.
But yes, "crtc_state->base.active" is at offset 9 from "crtc_state", so it's pretty clearly just that change frm
if (intel_crtc->active) {
if (crtc_state->base.active) {and "crtc_state" is NULL.
And the code very much knows that crtc_state can be NULL, since it's initialized with
crtc_state = state->base.state ? intel_atomic_get_crtc_state(state->base.state,intel_crtc) : NULL;
Tssk. Daniel? Should I just revert that commit dec4f799d0a4 ("drm/i915: Use crtc_state->active in primary check_plane func") for now, or is there a better fix? Like just checking crtc_state for NULL?
Linus
More symbols would be nice.
With the transitional helpers when crtc_state == NULL you don't want to update the scalers or funny things happen. Fix is probably something like this:
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index ba9321998a41..830e07b23a15 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -13276,7 +13276,7 @@ intel_check_primary_plane(struct drm_plane *plane, if (ret) return ret;
- if (crtc_state->base.active) { + if (crtc_state ? crtc_state->base.active || crtc->state->active) { struct intel_plane_state *old_state = to_intel_plane_state(plane->state);