In 64bit system, if you set CONFIG_CMA_SIZE_MBYTES>=2048, it will overflow and size_bytes will be a big wrong number. Set CONFIG_CMA_SIZE_MBYTES=2048 and you will get an info below during system boot: ********* cma: Failed to reserve 17592186042368 MiB ********* Signed-off-by: Tan Xiaojun <tanxiaojun@xxxxxxxxxx> --- drivers/base/dma-contiguous.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 950fff9..426ba27 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -46,7 +46,7 @@ struct cma *dma_contiguous_default_area; * Users, who want to set the size of global CMA area for their system * should use cma= kernel parameter. */ -static const phys_addr_t size_bytes = CMA_SIZE_MBYTES * SZ_1M; +static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; static phys_addr_t size_cmdline = -1; static phys_addr_t base_cmdline; static phys_addr_t limit_cmdline; -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>