drm/amdgpu: add missing lock to amdgpu_ttm_access_memory_sdma

commit 4fa944255be521b1bbd9780383f77206303a3a5c upstream.

Users of ttm entities need to hold the gtt_window_lock before using them
to guarantee proper ordering of jobs.

Cc: stable@vger.kernel.org
Fixes: cb5cc4f573e1 ("drm/amdgpu: improve debug VRAM access performance using sdma")
Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 1c8ac4cf08c5ac17d2655400753b83eb888dff39..af729cd521edf64e7e5e882b36f46865c5b425d2 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1513,6 +1513,7 @@ static int amdgpu_ttm_access_memory_sdma(struct ttm_buffer_object *bo,
        if (r)
                goto out;
 
+       mutex_lock(&adev->mman.gtt_window_lock);
        amdgpu_res_first(abo->tbo.resource, offset, len, &src_mm);
        src_addr = amdgpu_ttm_domain_start(adev, bo->resource->mem_type) +
                src_mm.start;
@@ -1527,6 +1528,7 @@ static int amdgpu_ttm_access_memory_sdma(struct ttm_buffer_object *bo,
        WARN_ON(job->ibs[0].length_dw > num_dw);
 
        fence = amdgpu_job_submit(job);
+       mutex_unlock(&adev->mman.gtt_window_lock);
 
        if (!dma_fence_wait_timeout(fence, false, adev->sdma_timeout))
                r = -ETIMEDOUT;