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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 2873FC55179 for ; Tue, 27 Oct 2020 08:11:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4F10207C3 for ; Tue, 27 Oct 2020 08:11:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2508756AbgJ0ILJ (ORCPT ); Tue, 27 Oct 2020 04:11:09 -0400 Received: from verein.lst.de ([213.95.11.211]:37795 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393441AbgJ0ILH (ORCPT ); Tue, 27 Oct 2020 04:11:07 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id C9A7967373; Tue, 27 Oct 2020 09:11:03 +0100 (CET) Date: Tue, 27 Oct 2020 09:11:03 +0100 From: "hch@lst.de" To: Parav Pandit Cc: Jakub Kicinski , syzbot , "christian.koenig@amd.com" , "dri-devel@lists.freedesktop.org" , "hch@lst.de" , "iommu@lists.linux-foundation.org" , "linaro-mm-sig-owner@lists.linaro.org" , "linaro-mm-sig@lists.linaro.org" , "linux-kernel@vger.kernel.org" , "linux-media@vger.kernel.org" , "m.szyprowski@samsung.com" , "netdev@vger.kernel.org" , "robin.murphy@arm.com" , "sumit.semwal@linaro.org" , "syzkaller-bugs@googlegroups.com" , "linux-rdma@vger.kernel.org" Subject: Re: WARNING in dma_map_page_attrs Message-ID: <20201027081103.GA22877@lst.de> References: <000000000000335adc05b23300f6@google.com> <000000000000a0f8a305b261fe4a@google.com> <20201024111516.59abc9ec@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Oct 26, 2020 at 05:23:48AM +0000, Parav Pandit wrote: > Hi Christoph, > > > From: Jakub Kicinski > > Sent: Saturday, October 24, 2020 11:45 PM > > > > CC: rdma, looks like rdma from the stack trace > > > > On Fri, 23 Oct 2020 20:07:17 -0700 syzbot wrote: > > > syzbot has found a reproducer for the following issue on: > > > > > > HEAD commit: 3cb12d27 Merge tag 'net-5.10-rc1' of git://git.kernel.org/.. > > In [1] you mentioned that dma_mask should not be set for dma_virt_ops. > So patch [2] removed it. > > But check to validate the dma mask for all dma_ops was added in [3]. > > What is the right way? Did I misunderstood your comment about dma_mask in [1]? No, I did not say we don't need the mask. I said copying over the various dma-related fields from the parent is bogus. I think rxe (and ther other drivers/infiniband/sw drivers) need a simple dma_coerce_mask_and_coherent and nothing else.