drm/nouveau: fix panels using straps-based mode detection

nouveau_bios_fp_mode() zeroes the mode struct before filling in relevant
entries.  This nukes the mode id initialised by drm_mode_create(), and
causes warnings from idr when we try to remove the mode.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 87186a4bbf03..fc737037f751 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -558,8 +558,10 @@ nouveau_connector_get_modes(struct drm_connector *connector)
         if (nv_encoder->dcb->type == OUTPUT_LVDS &&
             (nv_encoder->dcb->lvdsconf.use_straps_for_mode ||
              dev_priv->vbios.fp_no_ddc) && nouveau_bios_fp_mode(dev, NULL)) {
-                nv_connector->native_mode = drm_mode_create(dev);
-                nouveau_bios_fp_mode(dev, nv_connector->native_mode);
+                struct drm_display_mode mode;
+
+                nouveau_bios_fp_mode(dev, &mode);
+                nv_connector->native_mode = drm_mode_duplicate(dev, &mode);
         }
 
         /* Find the native mode if this is a digital panel, if we didn't