From: Timur Tabi
Date: Fri, 22 Sep 2017 15:32:44 -0500
> When mapping the RX DMA buffers, the driver was accidentally specifying
> zero for the buffer length. Under normal circumstances, SWIOTLB does not
> need to allocate a bounce buffer, so the address is just mapped
When mapping the RX DMA buffers, the driver was accidentally specifying
zero for the buffer length. Under normal circumstances, SWIOTLB does not
need to allocate a bounce buffer, so the address is just mapped without
checking the size field. This is why the error was not detected earlier.