We have below nested fence slot reservation and then fence addition to that dma_resv. dma_resv_reserve_fences() from --> ttm_bo_handle_move_mem() dma_resv_reserve_fences() from --> i915_vma_unbind_async() dma_resv_add_fence() from --> i915_vma_unbind_async() dma_resv_add_fence() from -->ttm_bo_move_accel_cleanup() A nested dma_resv_reserve_fences will not reserve extra slots and if the BO comes with lots of fences in its dma_resv, we might see: BUG_ON(fobj->num_fences >= fobj->max_fences); Suggested-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx> Signed-off-by: Nirmoy Das <nirmoy.das@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_vma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 7d044888ac33..5ac4c1c2403c 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -2149,7 +2149,7 @@ int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm) if (!obj->mm.rsgt) return -EBUSY; - err = dma_resv_reserve_fences(obj->base.resv, 1); + err = dma_resv_reserve_fences(obj->base.resv, 2); if (err) return -EBUSY; -- 2.38.0