From: Jeremy Cline
mainline inclusion
from mainline
commit aff2299e0d81b26304ccc6a1ec0170e437f38efc
issue: #I4NRS5
CVE: CVE-2020-27820
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
Nouveau does not currently support hot-unplugging, but it still makes
sense to switch from drm_dev_unregister() to drm_dev_unplug().
drm_dev_unplug() calls drm_dev_unregister() after marking the device as
unplugged, but only after any device critical sections are finished.
Since nouveau isn't using drm_dev_enter() and drm_dev_exit(), there are
no critical sections so this is nearly functionally equivalent. However,
the DRM layer does check to see if the device is unplugged, and if it is
returns appropriate error codes.
In the future nouveau can add critical sections in order to truly
support hot-unplugging.
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Jeremy Cline
Reviewed-by: Lyude Paul
Reviewed-by: Ben Skeggs
Tested-by: Karol Herbst
Signed-off-by: Karol Herbst
Link: https://patchwork.freedesktop.org/patch/msgid/20201125202648.5220-2-jcline@r...
Link: https://gitlab.freedesktop.org/drm/nouveau/-/merge_requests/14
Signed-off-by: Chen Jun
Reviewed-by: weiyang wang
Reviewed-by: Jason Yan
Signed-off-by: Chen Jun
Signed-off-by: Zheng Zengkai
Signed-off-by: Yu Changchun
---
drivers/gpu/drm/nouveau/nouveau_drm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 42fc5c813a9b..470b3c8f7392 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -792,7 +792,7 @@ nouveau_drm_device_remove(struct drm_device *dev)
struct nvkm_client *client;
struct nvkm_device *device;
- drm_dev_unregister(dev);
+ drm_dev_unplug(dev);
dev->irq_enabled = false;
client = nvxx_client(&drm->client.base);
--
2.25.1
