From fd5002d6a3c602664b07668a24df4ef7a43bf078 Mon Sep 17 00:00:00 2001
From: Felix Kuehling <Felix.Kuehling@amd.com>
Date: Wed, 17 Jan 2018 23:52:03 -0500
Subject: [PATCH] drm/ttm: Don't add swapped BOs to swap-LRU list
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Git-commit: fd5002d6a3c602664b07668a24df4ef7a43bf078
Patch-mainline: v4.16-rc1
References: bsc#1051510

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
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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
@@ -170,7 +170,8 @@ 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);