Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933783AbeALNQ5 (ORCPT + 1 other); Fri, 12 Jan 2018 08:16:57 -0500 Received: from mail-qt0-f195.google.com ([209.85.216.195]:46619 "EHLO mail-qt0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933462AbeALNQy (ORCPT ); Fri, 12 Jan 2018 08:16:54 -0500 X-Google-Smtp-Source: ACJfBosIJnvehbcZesAIlg3FnmupYOzJxD/5ZELthFKCLIXLRfBPNpU4Pn5uQMp7msA/ZNkw1emEwA== Date: Fri, 12 Jan 2018 08:16:48 -0500 From: Konrad Rzeszutek Wilk To: Christoph Hellwig Cc: iommu@lists.linux-foundation.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-c6x-dev@linux-c6x.org, linux-cris-kernel@axis.com, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-metag@vger.kernel.org, Michal Simek , linux-mips@linux-mips.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, patches@groups.riscv.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, Guan Xuetao , x86@kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 19/33] dma-mapping: warn when there is no coherent_dma_mask Message-ID: <20180112131646.GA26900@localhost.localdomain> References: <20180110080027.13879-1-hch@lst.de> <20180110080027.13879-20-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180110080027.13879-20-hch@lst.de> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Wed, Jan 10, 2018 at 09:00:13AM +0100, Christoph Hellwig wrote: > These days all devices should have a DMA coherent mask, and most dma_ops > implementations rely on that fact. But just to be sure add an assert to > ring the warning bell if that is not the case. > > Signed-off-by: Christoph Hellwig Reviewed-by: Konrad Rzeszutek Wilk > --- > include/linux/dma-mapping.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > index d84951865be7..9f28b2fa329e 100644 > --- a/include/linux/dma-mapping.h > +++ b/include/linux/dma-mapping.h > @@ -513,6 +513,7 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size, > void *cpu_addr; > > BUG_ON(!ops); > + WARN_ON_ONCE(!dev->coherent_dma_mask); > > if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) > return cpu_addr; > -- > 2.14.2 >