[PATCH] drm/vc4: Allocate the right amount of space for boot-time CRTC state.

[Eric Anholt]

Without this, the first modeset would dereference past the allocation
when trying to free the mm node.

Signed-off-by: Eric Anholt <e...@anholt.net>
Tested-by: Stefan Wahren <stefan.wah...@i2se.com>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 24edd0c22cc9..9d91a40e4345 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -845,6 +845,17 @@ static void vc4_crtc_destroy_state(struct drm_crtc *crtc,
        drm_atomic_helper_crtc_destroy_state(crtc, state);
 }
 
+static void
+vc4_crtc_reset(struct drm_crtc *crtc)
+{
+       if (crtc->state)
+               __drm_atomic_helper_crtc_destroy_state(crtc->state);
+
+       crtc->state = kzalloc(sizeof(struct vc4_crtc_state), GFP_KERNEL);
+       if (crtc->state)
+               crtc->state->crtc = crtc;
+}
+
 static const struct drm_crtc_funcs vc4_crtc_funcs = {
        .set_config = drm_atomic_helper_set_config,
        .destroy = vc4_crtc_destroy,
@@ -852,7 +863,7 @@ static const struct drm_crtc_funcs vc4_crtc_funcs = {
        .set_property = NULL,
        .cursor_set = NULL, /* handled by drm_mode_cursor_universal */
        .cursor_move = NULL, /* handled by drm_mode_cursor_universal */
-       .reset = drm_atomic_helper_crtc_reset,
+       .reset = vc4_crtc_reset,
        .atomic_duplicate_state = vc4_crtc_duplicate_state,
        .atomic_destroy_state = vc4_crtc_destroy_state,
        .gamma_set = vc4_crtc_gamma_set,
-- 
2.11.0