From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751684AbeCZNnC (ORCPT ); Mon, 26 Mar 2018 09:43:02 -0400 Received: from verein.lst.de ([213.95.11.211]:35421 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750955AbeCZNnB (ORCPT ); Mon, 26 Mar 2018 09:43:01 -0400 Date: Mon, 26 Mar 2018 15:42:59 +0200 From: Christoph Hellwig To: Konrad Rzeszutek Wilk Cc: Christoph Hellwig , tglx@linutronix.de, mingo@elte.hu, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Subject: Re: [PATCH] swiotlb: swiotlb_{alloc,free}_buffer should depend on CONFIG_DMA_DIRECT_OPS Message-ID: <20180326134259.GA15387@lst.de> References: <20180323174930.17767-1-hch@lst.de> <20180323185707.GD25533@char.us.oracle.com> <20180324170351.GA511@lst.de> <20180324200545.GC23658@char.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180324200545.GC23658@char.us.oracle.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 24, 2018 at 04:05:45PM -0400, Konrad Rzeszutek Wilk wrote: > > > > Otherwise we might get unused symbol warnings for configs that built > > > > swiotlb.c only for use by xen-swiotlb.c and that don't otherwise select > > > > CONFIG_DMA_DIRECT_OPS, which is possible on arm. > > > > > > > > Fixes: 16e73adbca76 ("dma/swiotlb: Remove swiotlb_{alloc,free}_coherent()") > > > > Reported-by: Stephen Rothwell > > > > Signed-off-by: Christoph Hellwig > > > > > > > > > Alternatively could we set the Kconfig to slect DMA_DIRECT_OPS? > > > > > > IFF we build swiotlb.c only for xen-swiotlb we don't need DMA_DIRECT_OPS. > > I don't think there is ever an case where you want a Xen specific build. arm never uses swiotlb directly, so any swiotlb.c build on arm is purely for xen-swiotlb.c From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH] swiotlb: swiotlb_{alloc,free}_buffer should depend on CONFIG_DMA_DIRECT_OPS Date: Mon, 26 Mar 2018 15:42:59 +0200 Message-ID: <20180326134259.GA15387@lst.de> References: <20180323174930.17767-1-hch@lst.de> <20180323185707.GD25533@char.us.oracle.com> <20180324170351.GA511@lst.de> <20180324200545.GC23658@char.us.oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20180324200545.GC23658-he5eyhs8q0BAdwtm4QZOy9BPR1lH4CV8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Konrad Rzeszutek Wilk Cc: tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, Christoph Hellwig , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Sat, Mar 24, 2018 at 04:05:45PM -0400, Konrad Rzeszutek Wilk wrote: > > > > Otherwise we might get unused symbol warnings for configs that built > > > > swiotlb.c only for use by xen-swiotlb.c and that don't otherwise select > > > > CONFIG_DMA_DIRECT_OPS, which is possible on arm. > > > > > > > > Fixes: 16e73adbca76 ("dma/swiotlb: Remove swiotlb_{alloc,free}_coherent()") > > > > Reported-by: Stephen Rothwell > > > > Signed-off-by: Christoph Hellwig > > > > > > > > > Alternatively could we set the Kconfig to slect DMA_DIRECT_OPS? > > > > > > IFF we build swiotlb.c only for xen-swiotlb we don't need DMA_DIRECT_OPS. > > I don't think there is ever an case where you want a Xen specific build. arm never uses swiotlb directly, so any swiotlb.c build on arm is purely for xen-swiotlb.c