drm/amdgpu/ttm: Fix memory leak userptr pages

stable inclusion
from stable-5.10.36
commit 14637a8dfe4f2ee3e2fa196ec7d71feff3343a09
bugzilla: 51867
CVE: NA

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

[ Upstream commit 0f6f9dd4 ]

If userptr pages have been pinned but not bounded,
they remain uncleared.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NDaniel Gomez <daniel@qtec.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

@@ -1254,13 +1254,13 @@ static void amdgpu_ttm_backend_unbind(struct ttm_bo_device *bdev,
 	struct amdgpu_ttm_tt *gtt = (void *)ttm;
 	int r;
 
-	if (!gtt->bound)
-		return;
-
 	/* if the pages have userptr pinning then clear that first */
 	if (gtt->userptr)
 		amdgpu_ttm_tt_unpin_userptr(bdev, ttm);
 
+	if (!gtt->bound)
+		return;
+
 	if (gtt->offset == AMDGPU_BO_INVALID_OFFSET)
 		return;