Hi Imre,

Thanks for the review.

On Wed, 10 Jun 2026 at 22:54, Imre Deak <[email protected]> wrote:
>
> On Wed, Jun 10, 2026 at 11:54:19AM +0800, Guangshuo Li wrote:
> > intel_crtc_free_hw_state() drops the CRTC color blob references, but
> > leaves the corresponding pointers unchanged.
> >
> > This can matter in intel_crtc_prepare_cleared_state(), which frees the
> > old CRTC hw state before calling intel_dp_tunnel_atomic_clear_stream_bw().
> > The latter can fail while looking up the DP tunnel group state, for
> > example with -EDEADLK.
> >
> > If that happens, the function returns without completing the cleared
> > state preparation. The failed atomic state will then be cleared by the
> > atomic core and intel_crtc_free_hw_state() can be called again for the
> > same state, dropping the same blob references again.
> >
> > Clear the blob pointers after dropping the references so repeated cleanup
> > of the same CRTC hw state is safe.
> >
> > Fixes: fb69d0076e68 ("drm/i915/dp_tunnel: Fix error handling when clearing 
> > stream BW in atomic state")
> > Suggested-by: Imre Deak <[email protected]>
> > Signed-off-by: Guangshuo Li <[email protected]>
> > ---
> > v2:
> >   - Keep the original ordering in intel_crtc_prepare_cleared_state().
> >   - Clear the blob reference pointers in intel_crtc_free_hw_state(), as
> >     suggested by Imre.
> >
> >  drivers/gpu/drm/i915/display/intel_atomic.c | 6 ++++++
> >  1 file changed, 6 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c 
> > b/drivers/gpu/drm/i915/display/intel_atomic.c
> > index 71b7325917b6..0cdae87e4bfc 100644
> > --- a/drivers/gpu/drm/i915/display/intel_atomic.c
> > +++ b/drivers/gpu/drm/i915/display/intel_atomic.c
> > @@ -294,6 +294,12 @@ static void intel_crtc_put_color_blobs(struct 
> > intel_crtc_state *crtc_state)
> >  void intel_crtc_free_hw_state(struct intel_crtc_state *crtc_state)
> >  {
> >       intel_crtc_put_color_blobs(crtc_state);
> > +
> > +     crtc_state->hw.degamma_lut = NULL;
> > +     crtc_state->hw.gamma_lut = NULL;
> > +     crtc_state->hw.ctm = NULL;
> > +     crtc_state->pre_csc_lut = NULL;
> > +     crtc_state->post_csc_lut = NULL;
> >  }
>
> Could you still move the clearing closer where the refs are dropped, to
> the end of intel_crtc_put_color_blobs()? Otherwise this looks ok to me.
>
> >
> >  /**
> > --
> > 2.43.0
> >

Sure, I'll move the pointer clearing to the end of
intel_crtc_put_color_blobs() and send a v3.

Best regards,
Guangshuo

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