On Fri, May 05, 2023 at 02:20:17PM +0300, Lisovskiy, Stanislav wrote:
> On Fri, May 05, 2023 at 02:06:34PM +0300, Ville Syrjälä wrote:
> > On Fri, May 05, 2023 at 02:05:27PM +0300, Lisovskiy, Stanislav wrote:
> > > On Fri, May 05, 2023 at 02:02:43PM +0300, Ville Syrjälä wrote:
> > > > On Fri, May 05, 2023 at 01:58:03PM +0300, Lisovskiy, Stanislav wrote:
> > > > > On Fri, May 05, 2023 at 01:54:14PM +0300, Ville Syrjälä wrote:
> > > > > > On Fri, May 05, 2023 at 11:22:12AM +0300, Stanislav Lisovskiy wrote:
> > > > > > > intel_atomic_get_new_crtc_state can return NULL, unless crtc
> > > > > > > state wasn't
> > > > > > > obtained previously with intel_atomic_get_crtc_state, so we must
> > > > > > > check it
> > > > > > > for NULLness here, just as in many other places, where we can't
> > > > > > > guarantee
> > > > > > > that intel_atomic_get_crtc_state was called.
> > > > > > > We are currently getting NULL ptr deref because of that, so this
> > > > > > > fix was
> > > > > > > confirmed to help.
> > > > > > >
> > > > > > > Fixes: 74a75dc90869 ("drm/i915/display: move plane
> > > > > > > prepare/cleanup to intel_atomic_plane.c")
> > > > > > > Signed-off-by: Stanislav Lisovskiy <stanislav.lisovs...@intel.com>
> > > > > > > ---
> > > > > > > drivers/gpu/drm/i915/display/intel_atomic_plane.c | 4 ++--
> > > > > > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > > > > > >
> > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > > > > > > b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > > > > > > index 9f670dcfe76e..4125ee07a271 100644
> > > > > > > --- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > > > > > > +++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
> > > > > > > @@ -1029,7 +1029,7 @@ intel_prepare_plane_fb(struct drm_plane
> > > > > > > *_plane,
> > > > > > > int ret;
> > > > > > >
> > > > > > > if (old_obj) {
> > > > > > > - const struct intel_crtc_state *crtc_state =
> > > > > > > + const struct intel_crtc_state *new_crtc_state =
> > > > > > > intel_atomic_get_new_crtc_state(state,
> > > > > > >
> > > > > > > to_intel_crtc(old_plane_state->hw.crtc));
> > > > > > >
> > > > > > > @@ -1044,7 +1044,7 @@ intel_prepare_plane_fb(struct drm_plane
> > > > > > > *_plane,
> > > > > > > * This should only fail upon a hung GPU, in which case
> > > > > > > we
> > > > > > > * can safely continue.
> > > > > > > */
> > > > > > > - if (intel_crtc_needs_modeset(crtc_state)) {
> > > > > > > + if (new_crtc_state &&
> > > > > > > intel_crtc_needs_modeset(new_crtc_state)) {
> > > > > >
> > > > > > NAK. We need to fix the bug instead of paparing over it.
> > > > >
> > > > > I had pushed this already.
> > > >
> > > > It didn't even finish CI. Please revert.
> > >
> > > Swati did run CI and verified that fix helps. I'm _not_ going to revert.
> >
> > Fine. I'll do it.
>
> Problem is that you don't even care to explain, why this fix is wrong, but
> simply
> act in authoritarian way, instead of having constructive discussion.
I've explanined this one about a hundred times. The NULL pointer should
not happen. Someone needs to actually analyze what is happening instead
of just adding randomg NULL checks all over the place.
> I told that we had verified the fix and that we always do those checks in
> many places anyway where we get new_crtc_state.
> However there were no even reasons to reject mentioned here.
> I don't really think that bringing personality traits and authoritarian
> discussion style is a professional behaviour.
> Thanks for cooperation.
>
> >
> > >
> > > >
> > > > > Moreover as I understand we need to check that new_crtc_state
> > > > > for being NULL anyway. We do check it for being NULL in other places.
> > > > > But if you have another solution - go for it.
> > > > >
> > > > > Stan
> > > > >
> > > > >
> > > > > >
> > > > > > > ret =
> > > > > > > i915_sw_fence_await_reservation(&state->commit_ready,
> > > > > > >
> > > > > > > old_obj->base.resv,
> > > > > > > false, 0,
> > > > > > > --
> > > > > > > 2.37.3
> > > > > >
> > > > > > --
> > > > > > Ville Syrjälä
> > > > > > Intel
> > > >
> > > > --
> > > > Ville Syrjälä
> > > > Intel
> >
> > --
> > Ville Syrjälä
> > Intel
--
Ville Syrjälä
Intel
