[PATCH] drm/ttm: fix leaking fences via ttm_buffer_object_transfer

[Alex Deucher]

From: Ahzo <Ahzo at tutanota.com>

Set the drm_device to NULL, so that the newly created buffer object
doesn't appear to use the embedded gem object.

This is necessary, because otherwise no corresponding dma_resv_fini for
the dma_resv_init is called, resulting in a memory leak.

The dma_resv_fini in ttm_bo_release_list is only called if the embedded
gem object is not used, which is determined by checking if the
drm_device is NULL.

Bug: https://gitlab.freedesktop.org/drm/amd/issues/958
Fixes: 1e053b10ba60 ("drm/ttm: use gem reservation object")
Signed-off-by: Ahzo <Ahzo at tutanota.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/ttm/ttm_bo_util.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index c8e359ded1df..44c1e7adfb7c 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -514,6 +514,7 @@ static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
 		fbo->base.base.resv = &fbo->base.base._resv;
 
 	dma_resv_init(&fbo->base.base._resv);
+	fbo->base.base.dev = NULL;
 	ret = dma_resv_trylock(&fbo->base.base._resv);
 	WARN_ON(!ret);
 
-- 
2.24.1