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=-8.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 49AC9C07E9B for ; Mon, 5 Jul 2021 19:04:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DEF461986 for ; Mon, 5 Jul 2021 19:04:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229910AbhGETGm (ORCPT ); Mon, 5 Jul 2021 15:06:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:36488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229770AbhGETGm (ORCPT ); Mon, 5 Jul 2021 15:06:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D07161978; Mon, 5 Jul 2021 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625511844; bh=o012umLuvyjggdb73nB1nx1kOYsPv1SNeUIs18hDcAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GRwf1cGaUQnGNSK48BMiS8/L53RP5G/QW+0L7WarqJg3vdXhPi76IMHEfxJBcIPa3 O/IVWGS61Gw63qZ6P/lu+E1G7lOjBRQgMMYZUlxciRBcXpXeaEm0Nt8VlI20vyORW0 5Yt77iWQoVMzfxA0eNrndYooJS41ndFVzjZWCxmusBkktvSuT3rDjxcvXFg+FyE3zq Tiys8WKwLxyKU0wwkmXs/VX0V/xsNc/cZvd76dhCDw80UkiEfPmHKQyUCziEG4n9+X zngjj2Bp6GquWJbjoHo8XOCLo60dYdheBX5hvWTEA+kb21c5xQf9Khdj2j/E3DZMQq mzeeqFIjv4raA== Date: Mon, 5 Jul 2021 20:03:52 +0100 From: Will Deacon To: Nathan Chancellor Cc: Robin Murphy , Claire Chang , Rob Herring , mpe@ellerman.id.au, Joerg Roedel , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski , benh@kernel.crashing.org, paulus@samba.org, "list@263.net:IOMMU DRIVERS" , Stefano Stabellini , grant.likely@arm.com, xypron.glpk@gmx.de, Thierry Reding , mingo@kernel.org, bauerman@linux.ibm.com, peterz@infradead.org, Greg KH , Saravana Kannan , "Rafael J . Wysocki" , heikki.krogerus@linux.intel.com, Andy Shevchenko , Randy Dunlap , Dan Williams , Bartosz Golaszewski , linux-devicetree , lkml , linuxppc-dev@lists.ozlabs.org, xen-devel@lists.xenproject.org, Nicolas Boichat , Jim Quinlan , Tomasz Figa , bskeggs@redhat.com, Bjorn Helgaas , chris@chris-wilson.co.uk, Daniel Vetter , airlied@linux.ie, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, jani.nikula@linux.intel.com, Jianxiong Gao , joonas.lahtinen@linux.intel.com, linux-pci@vger.kernel.org, maarten.lankhorst@linux.intel.com, matthew.auld@intel.com, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com, Tom Lendacky , Qian Cai Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Message-ID: <20210705190352.GA19461@willie-the-truck> References: <20210624155526.2775863-7-tientzu@chromium.org> <20210630114348.GA8383@willie-the-truck> <20210701074045.GA9436@willie-the-truck> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Nathan, I may have just spotted something in these logs... On Fri, Jul 02, 2021 at 10:55:17PM -0700, Nathan Chancellor wrote: > [ 2.340956] pci 0000:0c:00.1: Adding to iommu group 4 > [ 2.340996] pci 0000:0c:00.2: Adding to iommu group 4 > [ 2.341038] pci 0000:0c:00.3: Adding to iommu group 4 > [ 2.341078] pci 0000:0c:00.4: Adding to iommu group 4 > [ 2.341122] pci 0000:0c:00.6: Adding to iommu group 4 > [ 2.341163] pci 0000:0d:00.0: Adding to iommu group 4 > [ 2.341203] pci 0000:0d:00.1: Adding to iommu group 4 > [ 2.361821] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 > [ 2.361839] pci 0000:00:00.2: AMD-Vi: Extended features (0x206d73ef22254ade): > [ 2.361846] PPR X2APIC NX GT IA GA PC GA_vAPIC > [ 2.361861] AMD-Vi: Interrupt remapping enabled > [ 2.361865] AMD-Vi: Virtual APIC enabled > [ 2.361870] AMD-Vi: X2APIC enabled > [ 2.362272] AMD-Vi: Lazy IO/TLB flushing enabled So at this point, the AMD IOMMU driver does: swiotlb = (iommu_default_passthrough() || sme_me_mask) ? 1 : 0; where 'swiotlb' is a global variable indicating whether or not swiotlb is in use. It's picked up a bit later on by pci_swiotlb_late_init(), which will call swiotlb_exit() if 'swiotlb' is false. Now, that used to work fine, because swiotlb_exit() clears 'io_tlb_default_mem' to NULL, but now with the restricted DMA changes, I think that all the devices which have successfully probed beforehand will have stale pointers to the freed structure in their 'dev->dma_io_tlb_mem' field. Will 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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 93410C07E99 for ; Mon, 5 Jul 2021 19:04:33 +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 E948961982 for ; Mon, 5 Jul 2021 19:04:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E948961982 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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 4GJZqg2mWsz3bYN for ; Tue, 6 Jul 2021 05:04:31 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=GRwf1cGa; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=will@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=GRwf1cGa; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (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 4GJZqB70MRz2yx2 for ; Tue, 6 Jul 2021 05:04:06 +1000 (AEST) Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D07161978; Mon, 5 Jul 2021 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625511844; bh=o012umLuvyjggdb73nB1nx1kOYsPv1SNeUIs18hDcAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GRwf1cGaUQnGNSK48BMiS8/L53RP5G/QW+0L7WarqJg3vdXhPi76IMHEfxJBcIPa3 O/IVWGS61Gw63qZ6P/lu+E1G7lOjBRQgMMYZUlxciRBcXpXeaEm0Nt8VlI20vyORW0 5Yt77iWQoVMzfxA0eNrndYooJS41ndFVzjZWCxmusBkktvSuT3rDjxcvXFg+FyE3zq Tiys8WKwLxyKU0wwkmXs/VX0V/xsNc/cZvd76dhCDw80UkiEfPmHKQyUCziEG4n9+X zngjj2Bp6GquWJbjoHo8XOCLo60dYdheBX5hvWTEA+kb21c5xQf9Khdj2j/E3DZMQq mzeeqFIjv4raA== Date: Mon, 5 Jul 2021 20:03:52 +0100 From: Will Deacon To: Nathan Chancellor Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Message-ID: <20210705190352.GA19461@willie-the-truck> References: <20210624155526.2775863-7-tientzu@chromium.org> <20210630114348.GA8383@willie-the-truck> <20210701074045.GA9436@willie-the-truck> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) 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, thomas.hellstrom@linux.intel.com, 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, Marek Szyprowski , Stefano Stabellini , Saravana Kannan , xypron.glpk@gmx.de, Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , Jianxiong Gao , Daniel Vetter , Konrad Rzeszutek Wilk , maarten.lankhorst@linux.intel.com, airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, Bjorn Helgaas , Claire Chang , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , Qian Cai , lkml , Tomasz Figa , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , Tom Lendacky , Robin Murphy , bauerman@linux.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Nathan, I may have just spotted something in these logs... On Fri, Jul 02, 2021 at 10:55:17PM -0700, Nathan Chancellor wrote: > [ 2.340956] pci 0000:0c:00.1: Adding to iommu group 4 > [ 2.340996] pci 0000:0c:00.2: Adding to iommu group 4 > [ 2.341038] pci 0000:0c:00.3: Adding to iommu group 4 > [ 2.341078] pci 0000:0c:00.4: Adding to iommu group 4 > [ 2.341122] pci 0000:0c:00.6: Adding to iommu group 4 > [ 2.341163] pci 0000:0d:00.0: Adding to iommu group 4 > [ 2.341203] pci 0000:0d:00.1: Adding to iommu group 4 > [ 2.361821] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 > [ 2.361839] pci 0000:00:00.2: AMD-Vi: Extended features (0x206d73ef22254ade): > [ 2.361846] PPR X2APIC NX GT IA GA PC GA_vAPIC > [ 2.361861] AMD-Vi: Interrupt remapping enabled > [ 2.361865] AMD-Vi: Virtual APIC enabled > [ 2.361870] AMD-Vi: X2APIC enabled > [ 2.362272] AMD-Vi: Lazy IO/TLB flushing enabled So at this point, the AMD IOMMU driver does: swiotlb = (iommu_default_passthrough() || sme_me_mask) ? 1 : 0; where 'swiotlb' is a global variable indicating whether or not swiotlb is in use. It's picked up a bit later on by pci_swiotlb_late_init(), which will call swiotlb_exit() if 'swiotlb' is false. Now, that used to work fine, because swiotlb_exit() clears 'io_tlb_default_mem' to NULL, but now with the restricted DMA changes, I think that all the devices which have successfully probed beforehand will have stale pointers to the freed structure in their 'dev->dma_io_tlb_mem' field. Will 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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 6C864C07E99 for ; Mon, 5 Jul 2021 19:04:09 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 0C18461987 for ; Mon, 5 Jul 2021 19:04:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C18461987 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id D4978605D7; Mon, 5 Jul 2021 19:04:08 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HOtdjPANgaW8; Mon, 5 Jul 2021 19:04:08 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp3.osuosl.org (Postfix) with ESMTPS id B985A60674; Mon, 5 Jul 2021 19:04:07 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 848AEC0010; Mon, 5 Jul 2021 19:04:07 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id D13ECC000E for ; Mon, 5 Jul 2021 19:04:06 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id BB9A883A92 for ; Mon, 5 Jul 2021 19:04:06 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Authentication-Results: smtp1.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=kernel.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id FcyRDKUSAdrJ for ; Mon, 5 Jul 2021 19:04:06 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp1.osuosl.org (Postfix) with ESMTPS id 3F16683A8E for ; Mon, 5 Jul 2021 19:04:04 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D07161978; Mon, 5 Jul 2021 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625511844; bh=o012umLuvyjggdb73nB1nx1kOYsPv1SNeUIs18hDcAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GRwf1cGaUQnGNSK48BMiS8/L53RP5G/QW+0L7WarqJg3vdXhPi76IMHEfxJBcIPa3 O/IVWGS61Gw63qZ6P/lu+E1G7lOjBRQgMMYZUlxciRBcXpXeaEm0Nt8VlI20vyORW0 5Yt77iWQoVMzfxA0eNrndYooJS41ndFVzjZWCxmusBkktvSuT3rDjxcvXFg+FyE3zq Tiys8WKwLxyKU0wwkmXs/VX0V/xsNc/cZvd76dhCDw80UkiEfPmHKQyUCziEG4n9+X zngjj2Bp6GquWJbjoHo8XOCLo60dYdheBX5hvWTEA+kb21c5xQf9Khdj2j/E3DZMQq mzeeqFIjv4raA== Date: Mon, 5 Jul 2021 20:03:52 +0100 From: Will Deacon To: Nathan Chancellor Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Message-ID: <20210705190352.GA19461@willie-the-truck> References: <20210624155526.2775863-7-tientzu@chromium.org> <20210630114348.GA8383@willie-the-truck> <20210701074045.GA9436@willie-the-truck> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, benh@kernel.crashing.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, Stefano Stabellini , Saravana Kannan , xypron.glpk@gmx.de, "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , Jianxiong Gao , Daniel Vetter , Konrad Rzeszutek Wilk , maarten.lankhorst@linux.intel.com, airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, Bjorn Helgaas , Claire Chang , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , Qian Cai , lkml , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , mpe@ellerman.id.au, Tom Lendacky , Robin Murphy , bauerman@linux.ibm.com X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi Nathan, I may have just spotted something in these logs... On Fri, Jul 02, 2021 at 10:55:17PM -0700, Nathan Chancellor wrote: > [ 2.340956] pci 0000:0c:00.1: Adding to iommu group 4 > [ 2.340996] pci 0000:0c:00.2: Adding to iommu group 4 > [ 2.341038] pci 0000:0c:00.3: Adding to iommu group 4 > [ 2.341078] pci 0000:0c:00.4: Adding to iommu group 4 > [ 2.341122] pci 0000:0c:00.6: Adding to iommu group 4 > [ 2.341163] pci 0000:0d:00.0: Adding to iommu group 4 > [ 2.341203] pci 0000:0d:00.1: Adding to iommu group 4 > [ 2.361821] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 > [ 2.361839] pci 0000:00:00.2: AMD-Vi: Extended features (0x206d73ef22254ade): > [ 2.361846] PPR X2APIC NX GT IA GA PC GA_vAPIC > [ 2.361861] AMD-Vi: Interrupt remapping enabled > [ 2.361865] AMD-Vi: Virtual APIC enabled > [ 2.361870] AMD-Vi: X2APIC enabled > [ 2.362272] AMD-Vi: Lazy IO/TLB flushing enabled So at this point, the AMD IOMMU driver does: swiotlb = (iommu_default_passthrough() || sme_me_mask) ? 1 : 0; where 'swiotlb' is a global variable indicating whether or not swiotlb is in use. It's picked up a bit later on by pci_swiotlb_late_init(), which will call swiotlb_exit() if 'swiotlb' is false. Now, that used to work fine, because swiotlb_exit() clears 'io_tlb_default_mem' to NULL, but now with the restricted DMA changes, I think that all the devices which have successfully probed beforehand will have stale pointers to the freed structure in their 'dev->dma_io_tlb_mem' field. Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 BF1ECC07E9C for ; Mon, 5 Jul 2021 19:04:06 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 832CA61982 for ; Mon, 5 Jul 2021 19:04:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 832CA61982 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D22FC89944; Mon, 5 Jul 2021 19:04:05 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id D8AE789944; Mon, 5 Jul 2021 19:04:04 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D07161978; Mon, 5 Jul 2021 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625511844; bh=o012umLuvyjggdb73nB1nx1kOYsPv1SNeUIs18hDcAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GRwf1cGaUQnGNSK48BMiS8/L53RP5G/QW+0L7WarqJg3vdXhPi76IMHEfxJBcIPa3 O/IVWGS61Gw63qZ6P/lu+E1G7lOjBRQgMMYZUlxciRBcXpXeaEm0Nt8VlI20vyORW0 5Yt77iWQoVMzfxA0eNrndYooJS41ndFVzjZWCxmusBkktvSuT3rDjxcvXFg+FyE3zq Tiys8WKwLxyKU0wwkmXs/VX0V/xsNc/cZvd76dhCDw80UkiEfPmHKQyUCziEG4n9+X zngjj2Bp6GquWJbjoHo8XOCLo60dYdheBX5hvWTEA+kb21c5xQf9Khdj2j/E3DZMQq mzeeqFIjv4raA== Date: Mon, 5 Jul 2021 20:03:52 +0100 From: Will Deacon To: Nathan Chancellor Subject: Re: [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing Message-ID: <20210705190352.GA19461@willie-the-truck> References: <20210624155526.2775863-7-tientzu@chromium.org> <20210630114348.GA8383@willie-the-truck> <20210701074045.GA9436@willie-the-truck> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , Stefano Stabellini , Saravana Kannan , xypron.glpk@gmx.de, Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , Jianxiong Gao , Konrad Rzeszutek Wilk , airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, Rob Herring , rodrigo.vivi@intel.com, Bjorn Helgaas , Claire Chang , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , Qian Cai , lkml , Tomasz Figa , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , mpe@ellerman.id.au, Tom Lendacky , Robin Murphy , bauerman@linux.ibm.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Nathan, I may have just spotted something in these logs... On Fri, Jul 02, 2021 at 10:55:17PM -0700, Nathan Chancellor wrote: > [ 2.340956] pci 0000:0c:00.1: Adding to iommu group 4 > [ 2.340996] pci 0000:0c:00.2: Adding to iommu group 4 > [ 2.341038] pci 0000:0c:00.3: Adding to iommu group 4 > [ 2.341078] pci 0000:0c:00.4: Adding to iommu group 4 > [ 2.341122] pci 0000:0c:00.6: Adding to iommu group 4 > [ 2.341163] pci 0000:0d:00.0: Adding to iommu group 4 > [ 2.341203] pci 0000:0d:00.1: Adding to iommu group 4 > [ 2.361821] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 > [ 2.361839] pci 0000:00:00.2: AMD-Vi: Extended features (0x206d73ef22254ade): > [ 2.361846] PPR X2APIC NX GT IA GA PC GA_vAPIC > [ 2.361861] AMD-Vi: Interrupt remapping enabled > [ 2.361865] AMD-Vi: Virtual APIC enabled > [ 2.361870] AMD-Vi: X2APIC enabled > [ 2.362272] AMD-Vi: Lazy IO/TLB flushing enabled So at this point, the AMD IOMMU driver does: swiotlb = (iommu_default_passthrough() || sme_me_mask) ? 1 : 0; where 'swiotlb' is a global variable indicating whether or not swiotlb is in use. It's picked up a bit later on by pci_swiotlb_late_init(), which will call swiotlb_exit() if 'swiotlb' is false. Now, that used to work fine, because swiotlb_exit() clears 'io_tlb_default_mem' to NULL, but now with the restricted DMA changes, I think that all the devices which have successfully probed beforehand will have stale pointers to the freed structure in their 'dev->dma_io_tlb_mem' field. Will 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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 EB4B2C11F85 for ; Tue, 6 Jul 2021 12:02:39 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 BBB3E620DC for ; Tue, 6 Jul 2021 12:02:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBB3E620DC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C395F6E161; Tue, 6 Jul 2021 12:02:36 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id D8AE789944; Mon, 5 Jul 2021 19:04:04 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D07161978; Mon, 5 Jul 2021 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625511844; bh=o012umLuvyjggdb73nB1nx1kOYsPv1SNeUIs18hDcAw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GRwf1cGaUQnGNSK48BMiS8/L53RP5G/QW+0L7WarqJg3vdXhPi76IMHEfxJBcIPa3 O/IVWGS61Gw63qZ6P/lu+E1G7lOjBRQgMMYZUlxciRBcXpXeaEm0Nt8VlI20vyORW0 5Yt77iWQoVMzfxA0eNrndYooJS41ndFVzjZWCxmusBkktvSuT3rDjxcvXFg+FyE3zq Tiys8WKwLxyKU0wwkmXs/VX0V/xsNc/cZvd76dhCDw80UkiEfPmHKQyUCziEG4n9+X zngjj2Bp6GquWJbjoHo8XOCLo60dYdheBX5hvWTEA+kb21c5xQf9Khdj2j/E3DZMQq mzeeqFIjv4raA== Date: Mon, 5 Jul 2021 20:03:52 +0100 From: Will Deacon To: Nathan Chancellor Message-ID: <20210705190352.GA19461@willie-the-truck> References: <20210624155526.2775863-7-tientzu@chromium.org> <20210630114348.GA8383@willie-the-truck> <20210701074045.GA9436@willie-the-truck> <20210702135856.GB11132@willie-the-truck> <0f7bd903-e309-94a0-21d7-f0e8e9546018@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-Mailman-Approved-At: Tue, 06 Jul 2021 12:02:36 +0000 Subject: Re: [Intel-gfx] [PATCH v15 06/12] swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, benh@kernel.crashing.org, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , Stefano Stabellini , Saravana Kannan , xypron.glpk@gmx.de, Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , Jianxiong Gao , Konrad Rzeszutek Wilk , airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, Rob Herring , Bjorn Helgaas , Claire Chang , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , Qian Cai , lkml , Tomasz Figa , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , mpe@ellerman.id.au, Tom Lendacky , Robin Murphy , bauerman@linux.ibm.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Nathan, I may have just spotted something in these logs... On Fri, Jul 02, 2021 at 10:55:17PM -0700, Nathan Chancellor wrote: > [ 2.340956] pci 0000:0c:00.1: Adding to iommu group 4 > [ 2.340996] pci 0000:0c:00.2: Adding to iommu group 4 > [ 2.341038] pci 0000:0c:00.3: Adding to iommu group 4 > [ 2.341078] pci 0000:0c:00.4: Adding to iommu group 4 > [ 2.341122] pci 0000:0c:00.6: Adding to iommu group 4 > [ 2.341163] pci 0000:0d:00.0: Adding to iommu group 4 > [ 2.341203] pci 0000:0d:00.1: Adding to iommu group 4 > [ 2.361821] pci 0000:00:00.2: AMD-Vi: Found IOMMU cap 0x40 > [ 2.361839] pci 0000:00:00.2: AMD-Vi: Extended features (0x206d73ef22254ade): > [ 2.361846] PPR X2APIC NX GT IA GA PC GA_vAPIC > [ 2.361861] AMD-Vi: Interrupt remapping enabled > [ 2.361865] AMD-Vi: Virtual APIC enabled > [ 2.361870] AMD-Vi: X2APIC enabled > [ 2.362272] AMD-Vi: Lazy IO/TLB flushing enabled So at this point, the AMD IOMMU driver does: swiotlb = (iommu_default_passthrough() || sme_me_mask) ? 1 : 0; where 'swiotlb' is a global variable indicating whether or not swiotlb is in use. It's picked up a bit later on by pci_swiotlb_late_init(), which will call swiotlb_exit() if 'swiotlb' is false. Now, that used to work fine, because swiotlb_exit() clears 'io_tlb_default_mem' to NULL, but now with the restricted DMA changes, I think that all the devices which have successfully probed beforehand will have stale pointers to the freed structure in their 'dev->dma_io_tlb_mem' field. Will _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx