diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index e2869fb31140..5f8d010516f0 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -186,6 +186,13 @@ int dma_resv_reserve_fences(struct dma_resv *obj, unsigned int num_fences) dma_resv_assert_held(obj); + /* Driver and component code should never call this function with + * num_fences=0. If they do it usually points to bugs when calculating + * the number of needed fences dynamically. + */ + if (WARN_ON(!num_fences)) + return -EINVAL; + old = dma_resv_fences_list(obj); if (old && old->max_fences) { if ((old->num_fences + num_fences) <= old->max_fences)