diff options
| author | Lukas Wunner <lukas@wunner.de> | 2015-11-18 15:43:20 +0300 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-11-19 19:00:24 +0300 |
| commit | 54632abe8ca3db8621673b186c7cc0e869c0032f (patch) | |
| tree | b48e3fe26a194df46e96d51272b3de98363039d0 /drivers/gpu/drm/i915/intel_dp_mst.c | |
| parent | ce7f172856396d92e82cb0eae420f4ce41c92851 (diff) | |
| download | linux-54632abe8ca3db8621673b186c7cc0e869c0032f.tar.xz | |
drm/i915: Fix oops caused by fbdev initialization failure
intelfb_create() is called once on driver initialization. If it fails,
ifbdev->helper.fbdev, ifbdev->fb or ifbdev->fb->obj may be NULL.
Further up in the call stack, intel_fbdev_initial_config() calls
intel_fbdev_fini() to tear down the ifbdev on failure. This calls
intel_fbdev_destroy() which dereferences ifbdev->fb. Fix the ensuing
oops.
Also check in these functions if ifbdev is not NULL to avoid oops:
i915_gem_framebuffer_info() is called on access to debugfs file
"i915_gem_framebuffer" and dereferences ifbdev, ifbdev->helper.fb
and ifbdev->helper.fb->obj.
intel_connector_add_to_fbdev() / intel_connector_remove_from_fbdev()
are called when registering / unregistering an mst connector and
dereference ifbdev.
v3: Drop additional null pointer checks in intel_fbdev_set_suspend(),
intel_fbdev_output_poll_changed() and intel_fbdev_restore_mode()
since they already check if ifbdev is not NULL, which is sufficient
now that intel_fbdev_fini() is called on initialization failure.
(Requested by Daniel Vetter <daniel.vetter@ffwll.ch>)
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: http://patchwork.freedesktop.org/patch/msgid/d05f0edf121264a9d0adb8ca713fd8cc4ae068bf.1447938059.git.lukas@wunner.de
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp_mst.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp_mst.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index 8a604ac797aa..a12d1c7ee0e7 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -408,7 +408,10 @@ static void intel_connector_add_to_fbdev(struct intel_connector *connector) { #ifdef CONFIG_DRM_FBDEV_EMULATION struct drm_i915_private *dev_priv = to_i915(connector->base.dev); - drm_fb_helper_add_one_connector(&dev_priv->fbdev->helper, &connector->base); + + if (dev_priv->fbdev) + drm_fb_helper_add_one_connector(&dev_priv->fbdev->helper, + &connector->base); #endif } @@ -416,7 +419,10 @@ static void intel_connector_remove_from_fbdev(struct intel_connector *connector) { #ifdef CONFIG_DRM_FBDEV_EMULATION struct drm_i915_private *dev_priv = to_i915(connector->base.dev); - drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper, &connector->base); + + if (dev_priv->fbdev) + drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper, + &connector->base); #endif } |