[PATCH AUTOSEL 6.1 39/39] drm/amdgpu: Reserve fences for VM update

[Sasha Levin]

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

[ Upstream commit 316baf09d355aec1179981b6dfe28eba50c5ee5b ]

In amdgpu_dma_buf_move_notify reserve fences for the page table updates
in amdgpu_vm_clear_freed and amdgpu_vm_handle_moved. This fixes a BUG_ON
in dma_resv_add_fence when using SDMA for page table updates.

Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index 7bd8e33b14be5..e8b3e9520cf6e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -400,7 +400,10 @@ amdgpu_dma_buf_move_notify(struct dma_buf_attachment *attach)
 				continue;
 		}
 
-		r = amdgpu_vm_clear_freed(adev, vm, NULL);
+		/* Reserve fences for two SDMA page table updates */
+		r = dma_resv_reserve_fences(resv, 2);
+		if (!r)
+			r = amdgpu_vm_clear_freed(adev, vm, NULL);
 		if (!r)
 			r = amdgpu_vm_handle_moved(adev, vm);
 
-- 
2.42.0