From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Courbot Subject: Re: linux-next: build failure after merge of the drm tree Date: Tue, 10 Nov 2015 13:55:37 +0900 Message-ID: References: <20151104202226.28468a03@canb.auug.org.au> <20151109164510.GA26721@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Received: from mail-ig0-f174.google.com ([209.85.213.174]:38460 "EHLO mail-ig0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751885AbbKJEz5 (ORCPT ); Mon, 9 Nov 2015 23:55:57 -0500 In-Reply-To: <20151109164510.GA26721@roeck-us.net> Sender: linux-next-owner@vger.kernel.org List-ID: To: Guenter Roeck Cc: Stephen Rothwell , Dave Airlie , linux-next , Linux Kernel Mailing List , Alexandre Courbot , Ben Skeggs On Tue, Nov 10, 2015 at 1:45 AM, Guenter Roeck wrote: > On Wed, Nov 04, 2015 at 08:22:26PM +1100, Stephen Rothwell wrote: >> Hi Dave, >> >> After merging the drm tree, today's linux-next build (s390 allmodconfig) >> failed like this: >> >> drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c:143:2: error: implicit declaration of function 'dma_to_phys' [-Werror=implicit-function-declaration] >> >> Caused by commit >> >> 69c4938249fb ("drm/nouveau/instmem/gk20a: use direct CPU access") >> >> Discovered after the release. >> > Still seen in next-20151109, affecting at least alpha, i386, parisc, s390, > and xtensa, but probably other architectures as well. > > dma_to_phys() was until now not used from driver code, and is only declared > for an architecture if it is used/needed there. Mmm there doesn't seem to be a portable way of getting a physical address from a DMA handle, which is what we are trying to do in this code. In that particular case a cast is enough though, so we should probably just do that. I will send a patch for Ben/David to include in order to fix this issue at least.