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, 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 47530C48BDF for ; Thu, 24 Jun 2021 05:43:50 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CDDDB613E7 for ; Thu, 24 Jun 2021 05:43:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDDDB613E7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4G9TZs1J2yz3bwn for ; Thu, 24 Jun 2021 15:43:49 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4G9TZQ2Gvgz2yWT for ; Thu, 24 Jun 2021 15:43:24 +1000 (AEST) Received: by verein.lst.de (Postfix, from userid 2407) id 6EF7567373; Thu, 24 Jun 2021 07:43:15 +0200 (CEST) Date: Thu, 24 Jun 2021 07:43:15 +0200 From: Christoph Hellwig To: Qian Cai Subject: Re: [PATCH v14 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Message-ID: <20210624054315.GA25381@lst.de> References: <20210619034043.199220-1-tientzu@chromium.org> <20210619034043.199220-7-tientzu@chromium.org> <76c3343d-72e5-9df3-8924-5474ee698ef4@quicinc.com> <20210623183736.GA472@willie-the-truck> <19d4c7a2-744d-21e0-289c-a576e1f0e6f3@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19d4c7a2-744d-21e0-289c-a576e1f0e6f3@quicinc.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, linux-devicetree , peterz@infradead.org, joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, jxgao@google.com, sstabellini@kernel.org, Saravana Kannan , Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Marek Szyprowski , Dan Williams , matthew.auld@intel.com, Nicolas Boichat , thomas.hellstrom@linux.intel.com, Jim Quinlan , Will Deacon , Konrad Rzeszutek Wilk , intel-gfx@lists.freedesktop.org, maarten.lankhorst@linux.intel.com, Robin Murphy , jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, bhelgaas@google.com, Claire Chang , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, airlied@linux.ie, Thierry Reding , Greg KH , Randy Dunlap , lkml , "list@263.net:IOMMU DRIVERS" , daniel@ffwll.ch, xypron.glpk@gmx.de, thomas.lendacky@amd.com, linuxppc-dev@lists.ozlabs.org, bauerman@linux.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Jun 23, 2021 at 02:44:34PM -0400, Qian Cai wrote: > is_swiotlb_force_bounce at /usr/src/linux-next/./include/linux/swiotlb.h:119 > > is_swiotlb_force_bounce() was the new function introduced in this patch here. > > +static inline bool is_swiotlb_force_bounce(struct device *dev) > +{ > + return dev->dma_io_tlb_mem->force_bounce; > +} To me the crash looks like dev->dma_io_tlb_mem is NULL. Can you turn this into : return dev->dma_io_tlb_mem && dev->dma_io_tlb_mem->force_bounce; for a quick debug check?