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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 C6AACC433B4 for ; Mon, 17 May 2021 13:11:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5697461028 for ; Mon, 17 May 2021 13:11:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5697461028 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id DD8A36B0036; Mon, 17 May 2021 09:11:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D890B6B006E; Mon, 17 May 2021 09:11:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C506D6B0070; Mon, 17 May 2021 09:11:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0020.hostedemail.com [216.40.44.20]) by kanga.kvack.org (Postfix) with ESMTP id 975EC6B0036 for ; Mon, 17 May 2021 09:11:43 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 2A9C5A8D0 for ; Mon, 17 May 2021 13:11:43 +0000 (UTC) X-FDA: 78150760086.04.C02AF24 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by imf19.hostedemail.com (Postfix) with ESMTP id 5B04390009E8 for ; Mon, 17 May 2021 13:11:41 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id E8EF168AFE; Mon, 17 May 2021 15:11:37 +0200 (CEST) Date: Mon, 17 May 2021 15:11:37 +0200 From: Christoph Hellwig To: Serge Belyshev Cc: Christoph Hellwig , Andrew Morton , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Peter Zijlstra , Daniel Vetter , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Chris Wilson , linux-mm@kvack.org Subject: Re: [PATCH 4/4] i915: fix remap_io_sg to verify the pgprot Message-ID: <20210517131137.GA19451@lst.de> References: <20210326055505.1424432-1-hch@lst.de> <20210326055505.1424432-5-hch@lst.de> <87pmxqiry6.fsf@depni.sinp.msu.ru> <20210517123716.GD15150@lst.de> <87lf8dik15.fsf@depni.sinp.msu.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87lf8dik15.fsf@depni.sinp.msu.ru> User-Agent: Mutt/1.5.17 (2007-11-01) X-Rspamd-Queue-Id: 5B04390009E8 Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=none; spf=none (imf19.hostedemail.com: domain of hch@lst.de has no SPF policy when checking 213.95.11.211) smtp.mailfrom=hch@lst.de X-Rspamd-Server: rspam04 X-Stat-Signature: n56xb4qiqyqry3h6w11brmrycw9s93zq X-HE-Tag: 1621257101-241920 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, May 17, 2021 at 04:09:42PM +0300, Serge Belyshev wrote: > Christoph Hellwig writes: > > > As an ad-hoc experiment: can you replace the call to remap_pfn_range > > with remap_pfn_range_notrack (and export it if you build i915 modular) > > in remap_io_sg and see if that makes any difference? > > That worked, thanks -- no artifacts seen. Looks like it is caused by the validation failure then. Which means the existing code is doing something wrong in its choice of the page protection bit. I really need help from the i915 maintainers here..