releases/4.19.51/drm-vc4-fix-fb-references-in-async-update.patch

   1 From c16b85559dcfb5a348cc085a7b4c75ed49b05e2c Mon Sep 17 00:00:00 2001
   2 From: Helen Koike <helen.koike@collabora.com>
   3 Date: Mon, 3 Jun 2019 13:56:09 -0300
   4 Subject: drm/vc4: fix fb references in async update
   5
   6 From: Helen Koike <helen.koike@collabora.com>
   7
   8 commit c16b85559dcfb5a348cc085a7b4c75ed49b05e2c upstream.
   9
  10 Async update callbacks are expected to set the old_fb in the new_state
  11 so prepare/cleanup framebuffers are balanced.
  12
  13 Calling drm_atomic_set_fb_for_plane() (which gets a reference of the new
  14 fb and put the old fb) is not required, as it's taken care by
  15 drm_mode_cursor_universal() when calling drm_atomic_helper_update_plane().
  16
  17 Cc: <stable@vger.kernel.org> # v4.19+
  18 Fixes: 539c320bfa97 ("drm/vc4: update cursors asynchronously through atomic")
  19 Suggested-by: Boris Brezillon <boris.brezillon@collabora.com>
  20 Signed-off-by: Helen Koike <helen.koike@collabora.com>
  21 Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
  22 Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
  23 Link: https://patchwork.freedesktop.org/patch/msgid/20190603165610.24614-5-helen.koike@collabora.com
  24 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  25
  26 ---
  27  drivers/gpu/drm/vc4/vc4_plane.c |    1 +
  28  1 file changed, 1 insertion(+)
  29
  30 --- a/drivers/gpu/drm/vc4/vc4_plane.c
  31 +++ b/drivers/gpu/drm/vc4/vc4_plane.c
  32 @@ -818,6 +818,7 @@ static void vc4_plane_atomic_async_updat
  33                 drm_atomic_set_fb_for_plane(plane->state, state->fb);
  34         }
  35
  36 +       swap(plane->state->fb, state->fb);
  37         /* Set the cursor's position on the screen.  This is the
  38          * expected change from the drm_mode_cursor_universal()
  39          * helper.