On Fri, Jul 26, 2019 at 06:00:57AM -0400, Suganath Prabu wrote: > Although SAS3 & SAS3.5 IT HBA controllers support > 64-bit DMA addressing, as per hardware design, > DMA address with all 64-bits set (0xFFFFFFFF-FFFFFFFF) > results in a firmware fault. Linux will never send a dma address with all bits set anyway, as that is our magic escape for the dma_addr_t error value. Additionally to generate that address you'd need a 1-byte sized, 1-byte aligned buffer, which we never use.