[PATCH 4.19 19/67] drm/ttm: fix LRU handling in ttm_buffer_object_transfer

From: Greg Kroah-Hartman
Date: Thu Dec 20 2018 - 04:29:20 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit d6e820fcd4cf08b11d291a1dd7bbd0636914647c ]

We need to set the NO_EVICT flag on the ghost object or otherwise we are
adding it to the LRU.

When it is added to the LRU we can run into a race between destroying
and evicting it again.

Signed-off-by: Christian KÃnig <christian.koenig@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo_util.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 046a6dda690a..40904e84f883 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -492,8 +492,10 @@ static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
if (!fbo)
return -ENOMEM;

- ttm_bo_get(bo);
fbo->base = *bo;
+ fbo->base.mem.placement |= TTM_PL_FLAG_NO_EVICT;
+
+ ttm_bo_get(bo);
fbo->bo = bo;

/**
--
2.19.1