drm/amdgpu: amdgpu_ttm_gart_bind set gtt bound flag

[ Upstream commit 6c6064cbe58b43533e3451ad6a8ba9736c109ac3 ]

Otherwise after the GTT bo is released, the GTT and gart space is freed
but amdgpu_ttm_backend_unbind will not clear the gart page table entry
and leave valid mapping entry pointing to the stale system page. Then
if GPU access the gart address mistakely, it will read undefined value
instead page fault, harder to debug and reproduce the real issue.

Cc: stable@vger.kernel.org
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 75c9fd2c6c2a1cb4cc39689668f2f65f036e55c5..b0ed10f4de609d97335c61134c7d6421339cb5b9 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -869,6 +869,7 @@ static void amdgpu_ttm_gart_bind(struct amdgpu_device *adev,
                amdgpu_gart_bind(adev, gtt->offset, ttm->num_pages,
                                 gtt->ttm.dma_address, flags);
        }
+       gtt->bound = true;
 }
 
 /*