From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ABF97C4727E for ; Wed, 30 Sep 2020 13:33:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DAAF20754 for ; Wed, 30 Sep 2020 13:33:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="lxYQCYkS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730048AbgI3Nd1 (ORCPT ); Wed, 30 Sep 2020 09:33:27 -0400 Received: from crapouillou.net ([89.234.176.41]:57212 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729663AbgI3Nd1 (ORCPT ); Wed, 30 Sep 2020 09:33:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1601472804; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ecNy/ZxFnTbjbqIO9nlUei1JR0PPL4AarFwXzFKz9CI=; b=lxYQCYkS2XdyqSqq16yw9/T40tnQonUGTBT6Sv19anGho7VUp97RwFz4qhnHgq1E9+MtLF v08Kd9A3oakGolE3MCiGYlzZpXxo5iHj5FyOzgqTweF97cPa8pGejg52DFJ5KEOpNBHrog e+Js9L8qS1uQsNBoXvJoJRJUqwxI91Y= Date: Wed, 30 Sep 2020 15:33:13 +0200 From: Paul Cercueil Subject: Re: linux-next: build failure after merge of the drm tree To: Christoph Hellwig Cc: Stephen Rothwell , Dave Airlie , DRI , Linux Next Mailing List , Linux Kernel Mailing List Message-Id: In-Reply-To: <20200930090252.GA9357@lst.de> References: <20200928135405.73404219@canb.auug.org.au> <20200928060427.GA15041@lst.de> <20200928113415.GA555@lst.de> <72ADHQ.T6LL1SHQF0RG3@crapouillou.net> <20200928121002.GA3219@lst.de> <20200930090252.GA9357@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-next@vger.kernel.org Hi Christoph, Le mer. 30 sept. 2020 =E0 11:02, Christoph Hellwig a =E9crit=20 : > On Mon, Sep 28, 2020 at 03:31:28PM +0200, Paul Cercueil wrote: >> It's allocated with dma_alloc_wc, but then it's only accessed as >> non-coherent. >>=20 >> Anyway, for the time being I guess you could revert 37054fc81443.=20 >> But I >> have patches on top of it in drm-misc-next so it's going to be a=20 >> mess. >>=20 >> If we have time I can come up with a custom dumb_create() fonction,=20 >> to make >> sure that the GEM buffers are allocated with=20 >> dma_alloc_noncoherent(). Is >> there a dma_mmap_noncoherent() too? >=20 > Please use the lower-level dma_alloc_pages and then just insert the > pages directly using remap_pfn_range. Although it might make sense > to eventually create a wrapper around remap_pfn_range for all the > vma sizing sanity checks. One thing missing for remap_pfn_range(), I have no alternative for this: vma->vm_page_prot =3D dma_pgprot(dev, vma->vm_page_prot,=20 DMA_ATTR_NON_CONSISTENT); So I have to do: vma->vm_page_prot =3D pgprot_noncached(vma->vm_page_prot); pgprot_val(vma->vm_page_prot) &=3D ~_CACHE_MASK; pgprot_val(vma->vm_page_prot) |=3D _CACHE_CACHABLE_NONCOHERENT; And that will only compile on MIPS, because these _CACHE_* macros are=20 only defined there. I would need something like a pgprot_noncoherent(), I think. -Paul