If the fbdev probing fails, and in our error path we fail to clear the
dev_priv->fbdev, then we can try and use a dangling fbdev pointer, and
in particular a NULL fb. This could also happen in pathological cases
where we try to operate on the fbdev prior to it being probed.
Reported-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxx>
---
drivers/gpu/drm/i915/intel_fbdev.c | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
index ef17d88a1bc7..23129dcfba9d 100644
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -782,7 +782,7 @@ void intel_fbdev_set_suspend(struct drm_device *dev, int state, bool synchronous
struct intel_fbdev *ifbdev = dev_priv->fbdev;
struct fb_info *info;
- if (!ifbdev)
+ if (!ifbdev || !ifbdev->fb)
return;
info = ifbdev->helper.fbdev;
@@ -827,31 +827,28 @@ void intel_fbdev_set_suspend(struct drm_device *dev, int state, bool synchronous
void intel_fbdev_output_poll_changed(struct drm_device *dev)
{
- struct drm_i915_private *dev_priv = to_i915(dev);
- if (dev_priv->fbdev)
- drm_fb_helper_hotplug_event(&dev_priv->fbdev->helper);
+ struct intel_fbdev *ifbdev = to_i915(dev)->fbdev;
+
+ if (ifbdev && ifbdev->fb)
+ drm_fb_helper_hotplug_event(&ifbdev->helper);
}
void intel_fbdev_restore_mode(struct drm_device *dev)
{
- int ret;
- struct drm_i915_private *dev_priv = to_i915(dev);
- struct intel_fbdev *ifbdev = dev_priv->fbdev;
- struct drm_fb_helper *fb_helper;
+ struct intel_fbdev *ifbdev = to_i915(dev)->fbdev;
if (!ifbdev)
return;
intel_fbdev_sync(ifbdev);
+ if (!ifbdev->fb)
+ return;
- fb_helper = &ifbdev->helper;
-
- ret = drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
- if (ret) {
+ if (drm_fb_helper_restore_fbdev_mode_unlocked(&ifbdev->helper)) {
DRM_DEBUG("failed to restore crtc mode\n");
} else {
- mutex_lock(&fb_helper->dev->struct_mutex);
+ mutex_lock(&dev->struct_mutex);
intel_fb_obj_invalidate(ifbdev->fb->obj, ORIGIN_GTT);
- mutex_unlock(&fb_helper->dev->struct_mutex);
+ mutex_unlock(&dev->struct_mutex);
}
}
--
2.8.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
