On Mon, Nov 19, 2018 at 03:22:13PM -0800, John Stultz wrote: > > + sg->dma_address = dma_addr; > > sg_dma_len(sg) = sg->length; > > } > > I know Robin has already replied with more detailed info, but just to > close the loop as I'm finally home, applying this patch didn't seem to > help with the IO hangs I'm seeing w/ HiKey960.
If Robins observation is right this should fix the problem for you: diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index bd73e7a91410..1833f0c1fba0 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -5,7 +5,7 @@ #include <linux/dma-mapping.h> #include <linux/mem_encrypt.h> -#define DIRECT_MAPPING_ERROR 0 +#define DIRECT_MAPPING_ERROR (~(dma_addr_t)0x0) #ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA #include <asm/dma-direct.h>
