There's at least one system that does not interpret the value of the device's 'startadd' field correctly, which leads to incorrectly displayed scanout buffers. Always placing the active scanout buffer at offset 0 works around the problem. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reported-by: John Donnelly <john.p.donnelly@oracle.com> Tested-by: John Donnelly <john.p.donnelly@oracle.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Fixes: 81da87f63a1e ("drm: Replace drm_gem_vram_push_to_system() with kunmap + unpin") Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: David Airlie <airlied@linux.ie> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: "Y.C. Chen" <yc_chen@aspeedtech.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "José Roberto de Souza" <jose.souza@intel.com> Cc: Andrzej Pietrasiewicz <andrzej.p@collabora.com> Cc: dri-devel@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v5.3+ Link: https://gitlab.freedesktop.org/drm/misc/issues/7 Link: https://patchwork.freedesktop.org/patch/msgid/20191126101529.20356-4-tzimmermann@suse.de