The openrisc DMA code supports DMA_ATTR_NON_CONSISTENT allocations, but does not provide a cache_sync operation. This means any user of it will never be able to actually transfer cache ownership and thus cause coherency bugs. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- arch/openrisc/kernel/dma.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c index f79457cb3741..9f25fd0fbb5d 100644 --- a/arch/openrisc/kernel/dma.c +++ b/arch/openrisc/kernel/dma.c @@ -98,15 +98,13 @@ arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, va = (unsigned long)page; - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) { - /* - * We need to iterate through the pages, clearing the dcache for - * them and setting the cache-inhibit bit. - */ - if (walk_page_range(va, va + size, &walk)) { - free_pages_exact(page, size); - return NULL; - } + /* + * We need to iterate through the pages, clearing the dcache for + * them and setting the cache-inhibit bit. + */ + if (walk_page_range(va, va + size, &walk)) { + free_pages_exact(page, size); + return NULL; } return (void *)va; @@ -122,10 +120,8 @@ arch_dma_free(struct device *dev, size_t size, void *vaddr, .mm = &init_mm }; - if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) { - /* walk_page_range shouldn't be able to fail here */ - WARN_ON(walk_page_range(va, va + size, &walk)); - } + /* walk_page_range shouldn't be able to fail here */ + WARN_ON(walk_page_range(va, va + size, &walk)); free_pages_exact(vaddr, size); } -- 2.20.1