qxl: fix framebuffer unpinning

BugLink: http://bugs.launchpad.net/bugs/1711358
qxl_plane_cleanup_fb() unpins the just activated framebuffer
instead of the old one.  Oops.  Fix it.

Cc: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Fixes: 1277eed5fecb8830c8cc414ad70c1ef640464bc0
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170918074145.2257-1-kraxel@redhat.com
(cherry picked from commit 5f3d862a736398e7068fa67142133f1713fdee8c)
Acked-by: Kamal Mostafa <kamal@canonical.com>
Acked-by: Andy Whitcroft <apw@canonical.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index 03fe182203ce9122abfe37bc3a1afcc16971ca4c..274df74a128c387a7694b3273c251234ddcefaa0 100644 (file)
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -701,14 +701,15 @@ static void qxl_plane_cleanup_fb(struct drm_plane *plane,
        struct drm_gem_object *obj;
        struct qxl_bo *user_bo;
 
-       if (!plane->state->fb) {
-               /* we never executed prepare_fb, so there's nothing to
+       if (!old_state->fb) {
+               /*
+                * we never executed prepare_fb, so there's nothing to
                 * unpin.
                 */
                return;
        }
 
-       obj = to_qxl_framebuffer(plane->state->fb)->obj;
+       obj = to_qxl_framebuffer(old_state->fb)->obj;
        user_bo = gem_to_qxl_bo(obj);
        qxl_bo_unpin(user_bo);
 }