From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754244AbbGaRqh (ORCPT ); Fri, 31 Jul 2015 13:46:37 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:37048 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753791AbbGaRqe convert rfc822-to-8bit (ORCPT ); Fri, 31 Jul 2015 13:46:34 -0400 From: Michal Nazarewicz To: Feng Tang Cc: "linux-kernel\@vger.kernel.org" , "m.szyprowski\@samsung.com" , "kyungmin.park\@samsung.com" , "akpm\@linux-foundation.org" , "iamjoonsoo.kim\@lge.com" Subject: Re: [PATCH] CMA: Don't return a valid cma for non-cma dev In-Reply-To: <20150731151816.GA18347@shbuild888> Organization: http://mina86.com/ References: <1438223828-26140-1-git-send-email-feng.tang@intel.com> <1438311070.4299.1.camel@intel.com> <20150731151816.GA18347@shbuild888> User-Agent: Notmuch/0.19+53~g2e63a09 (http://notmuchmail.org) Emacs/25.0.50.1 (x86_64-unknown-linux-gnu) X-Face: PbkBB1w#)bOqd`iCe"Ds{e+!C7`pkC9a|f)Qo^BMQvy\q5x3?vDQJeN(DS?|-^$uMti[3D*#^_Ts"pU$jBQLq~Ud6iNwAw_r_o_4]|JO?]}P_}Nc&"p#D(ZgUb4uCNPe7~a[DbPG0T~!&c.y$Ur,=N4RT>]dNpd;KFrfMCylc}gc??'U2j,!8%xdD Face: 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 X-PGP: 50751FF4 X-PGP-FP: AC1F 5F5C D418 88F8 CC84 5858 2060 4012 5075 1FF4 X-Hashcash: 1:20:150731:m.szyprowski@samsung.com::FpNUsNlONjIJ2mez:00000000000000000000000000000000000000UgT X-Hashcash: 1:20:150731:akpm@linux-foundation.org::QEU+mbHvlyoRVhmU:0000000000000000000000000000000000000hBU X-Hashcash: 1:20:150731:linux-kernel@vger.kernel.org::Ugf2YJGcd7UrM9Tr:0000000000000000000000000000000000MiJ X-Hashcash: 1:20:150731:iamjoonsoo.kim@lge.com::yKVKXUNmzGRY9kvq:0000000000000000000000000000000000000000/Sb X-Hashcash: 1:20:150731:feng.tang@intel.com::uEH/ZqIVRfg/wBMs:0000000000000000000000000000000000000000005SkY X-Hashcash: 1:20:150731:kyungmin.park@samsung.com::wv8Gr3vcrbK5RTxm:000000000000000000000000000000000000AYJr Date: Fri, 31 Jul 2015 19:46:30 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 31 2015, Feng Tang wrote: > Maybe I didn't make my problem clear, for our platform, we do need to > use cma as we have camera ISP which has no IOMMU, so we cannot set > "cma=0". Then specify a CMA region for the camera in platform initialisation code or device trees or whatever else is the rave nowadays. I’m assuming that you have a piece of code (or configuration of some sort) that assigns a CMA region to the device (otherwise ‘dev->cma_area’ would be NULL and your patch would just always get you NULL CMA area). Simply create a CMA area there and assign it to the device. -- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +------ooO--(_)--Ooo--