[PATCH] drm/nouveau: reorder nouveau_drm_device_fini

[Mark Menzynski]

Resources needed for output poll workers are destroyed in
nouveau_fbcon_fini() before output poll workers are cleared in
nouveau_display_fini(). This means there is a time between fbcon_fini
and display_fini, where if output poll happens, it crashes.

BUG: KASAN: use-after-free in
__drm_fb_helper_initial_config_and_unlock.cold+0x1f3/0x291
[drm_kms_helper]

Cc: Ben Skeggs <bske...@redhat.com>
Cc: Karol Herbst <kher...@redhat.com>
Cc: Lyude Paul <ly...@redhat.com>
Cc: David Airlie <airl...@linux.ie>
Cc: Daniel Vetter <dan...@ffwll.ch>
Cc: Sumit Semwal <sumit.sem...@linaro.org>
Cc: "Christian König" <christian.koe...@amd.com>
Cc: dri-devel@lists.freedesktop.org
Cc: nouv...@lists.freedesktop.org
Cc: linux-ker...@vger.kernel.org
Cc: linux-me...@vger.kernel.org
Cc: linaro-mm-...@lists.linaro.org
Signed-off-by: Mark Menzynski <mmenz...@redhat.com>
---
 drivers/gpu/drm/nouveau/nouveau_drm.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c 
b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 561309d447e0..773efdd20d2f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -588,12 +588,6 @@ nouveau_drm_device_init(struct drm_device *dev)
        if (ret)
                goto fail_dispctor;
 
-       if (dev->mode_config.num_crtc) {
-               ret = nouveau_display_init(dev, false, false);
-               if (ret)
-                       goto fail_dispinit;
-       }
-
        nouveau_debugfs_init(drm);
        nouveau_hwmon_init(dev);
        nouveau_svm_init(drm);
@@ -601,6 +595,12 @@ nouveau_drm_device_init(struct drm_device *dev)
        nouveau_fbcon_init(dev);
        nouveau_led_init(dev);
 
+       if (dev->mode_config.num_crtc) {
+               ret = nouveau_display_init(dev, false, false);
+               if (ret)
+                       goto fail_dispinit;
+       }
+
        if (nouveau_pmops_runtime()) {
                pm_runtime_use_autosuspend(dev->dev);
                pm_runtime_set_autosuspend_delay(dev->dev, 5000);
@@ -641,15 +641,14 @@ nouveau_drm_device_fini(struct drm_device *dev)
                pm_runtime_forbid(dev->dev);
        }
 
+       if (dev->mode_config.num_crtc)
+               nouveau_display_fini(dev, false, false);
        nouveau_led_fini(dev);
        nouveau_fbcon_fini(dev);
        nouveau_dmem_fini(drm);
        nouveau_svm_fini(drm);
        nouveau_hwmon_fini(dev);
        nouveau_debugfs_fini(drm);
-
-       if (dev->mode_config.num_crtc)
-               nouveau_display_fini(dev, false, false);
        nouveau_display_destroy(dev);
 
        nouveau_accel_fini(drm);
-- 
2.32.0