[PATCH 4.14 090/167] drm/ttm: Dont add swapped BOs to swap-LRU list

Greg Kroah-Hartman
2018-02-21T12:48:21Z

From: Felix Kuehling <Felix.Kuehling@amd.com>

commit fd5002d6a3c602664b07668a24df4ef7a43bf078 upstream.

A BO that's already swapped would be added back to the swap-LRU list
for example if its validation failed under high memory pressure. This
could later lead to swapping it out again and leaking previous swap
storage.

This commit adds a condition to prevent that from happening.

v2: Check page_flags instead of swap_storage

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/ttm/ttm_bo.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -175,7 +175,8 @@ void ttm_bo_add_to_lru(struct ttm_buffer
list_add_tail(&bo->lru, &man->lru[bo->priority]);
kref_get(&bo->list_kref);

- if (bo->ttm && !(bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
+ if (bo->ttm && !(bo->ttm->page_flags &
+ (TTM_PAGE_FLAG_SG | TTM_PAGE_FLAG_SWAPPED))) {
list_add_tail(&bo->swap,
&bo->glob->swap_lru[bo->priority]);
kref_get(&bo->list_kref);