[PATCH 4/4] qxl: fix qxl_conn_get_modes

[Gerd Hoffmann]

Call qxl_add_monitors_config_modes() unconditionally.  Do all sanity
checks in that function.

Fix sanity checks.  monitors_config is the current monitor
configuration, whereas client_monitors_config is the configuration
requested by the spice client.  So when filling the mode list, based on
the spice client request, we need to look at
client_monitors_config->count not monitors_config->count.

Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
---
 drivers/gpu/drm/qxl/qxl_display.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_display.c 
b/drivers/gpu/drm/qxl/qxl_display.c
index cf99ace..9548bb5 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -202,9 +202,17 @@ static int qxl_add_monitors_config_modes(struct 
drm_connector *connector,
        struct drm_display_mode *mode = NULL;
        struct qxl_head *head;
 
+       if (!qdev->monitors_config)
+               return 0;
+       if (h >= qdev->monitors_config->max_allowed)
+               return 0;
        if (!qdev->client_monitors_config)
                return 0;
+       if (h >= qdev->client_monitors_config->count)
+               return 0;
+
        head = &qdev->client_monitors_config->heads[h];
+       DRM_DEBUG_KMS("head %d is %dx%d\n", h, head->width, head->height);
 
        mode = drm_cvt_mode(dev, head->width, head->height, 60, false, false,
                            false);
@@ -911,19 +919,13 @@ static void qxl_enc_mode_set(struct drm_encoder *encoder,
 
 static int qxl_conn_get_modes(struct drm_connector *connector)
 {
-       int ret = 0;
-       struct qxl_device *qdev = connector->dev->dev_private;
        unsigned pwidth = 1024;
        unsigned pheight = 768;
+       int ret = 0;
 
-       DRM_DEBUG_KMS("monitors_config=%p\n", qdev->monitors_config);
-       /* TODO: what should we do here? only show the configured modes for the
-        * device, or allow the full list, or both? */
-       if (qdev->monitors_config && qdev->monitors_config->count) {
-               ret = qxl_add_monitors_config_modes(connector, &pwidth, 
&pheight);
-               if (ret < 0)
-                       return ret;
-       }
+       ret = qxl_add_monitors_config_modes(connector, &pwidth, &pheight);
+       if (ret < 0)
+               return ret;
        ret += qxl_add_common_modes(connector, pwidth, pheight);
        return ret;
 }
-- 
1.8.3.1