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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 9CA86C43334 for ; Wed, 20 Jul 2022 20:08:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E4DE111B4E3; Wed, 20 Jul 2022 20:08:35 +0000 (UTC) Received: from NAM12-DM6-obe.outbound.protection.outlook.com (mail-dm6nam12on2071.outbound.protection.outlook.com [40.107.243.71]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6D0BB11B4E3; Wed, 20 Jul 2022 20:08:34 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=h7Vv1tHoh8XNfOkcW2qPnQ2GhdNEKsYx3Gy6duOarqMG8rE4bksOR27aELOzoKTfWZh16ypW4JnvU2PNbXadN9XarkyvaVvb1OHqmyj5Lwvauh+vPXzZZlld7fHBBOJGNzIXY7704c+GX/V/0utRMPdgWzaUO4eXCJo9xsyad1DkD5oheOZQjFcMNOYbMoe90mBe2RIn+i7iq7xpye64iNWBiaZl2RHB2pSq7zgBbCy5AEE/brmr4EgyBCTD1Crjt5HeAHXSEk3hQoQ9KqB/Pi1xW6hOLdVJbybK8yHnRANomD2uTdx+p7AnlgHpTsQCJEhJewVgcMb/Oyn6zr9yaw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=b/zNR3VeaxC/rjRF1MXukl3kHZ1v8pua346nG+LKAjqvJ3rxeJuuIh3RvcYdFG9k7tuuZT9k9osrUrWExQtiJTy8L6hIt6gxabXn/hA8W1Y+K5iEJcDpI+3nRaO3rL/vSbsuBWIjPEy3hvd+RNKi0mAsK8XnFpkOU+8CmCCqWzGtqk58s6/12XeRkSr0/Clsres67AydM6b+0WapsD/qTBc+zDgPe0OYKxzR4NltKMm5ktwA/yCvsu2mHEntVcpLkTq2zo8ZAIMJsrMcFIpnYzVUXFcXLrC+V4Z2sPAHKtjLZgdMxEq8E4nxeA4eiFtS6Xu8rN87MPpaYCEFsyhDIw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=D8WjuBh6ZGgKl1mZndxxpKc84EJIpcI4CNnoJH47MrzIVXF+85zd5vdBwioiJiZ7VKFK7IS3FmmIX84Pu872+1BW65aFY2tr9tqaWFz7P+AQtCr37wvlp32KX0wD8AHKV0yZpeTM1JVyqL8ipkMXtXajaSU9UMPquIeANRZ5XAN8Cn/FaDAZGIRrI/mCFtWmJayYlwY1ReRym8MkCT5ghiCwC/A90Og35pZV5DMhN/4ouuFXywtJOxW9meykusznPJfqUBjkId/0KkmwRhrfZtNAuNgd6lltpfVPkdvKp06nY+qh53cvNfO34qFu8R9VlypHZo+eR6pZLUJ8RP9OrA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) by MN2PR12MB4783.namprd12.prod.outlook.com (2603:10b6:208:3e::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5438.21; Wed, 20 Jul 2022 20:08:31 +0000 Received: from MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb]) by MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb%3]) with mapi id 15.20.5458.018; Wed, 20 Jul 2022 20:08:31 +0000 Date: Wed, 20 Jul 2022 17:08:29 -0300 From: Jason Gunthorpe To: Alex Williamson Message-ID: <20220720200829.GW4609@nvidia.com> References: <0-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <1-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <20220720134113.4225f9d6.alex.williamson@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220720134113.4225f9d6.alex.williamson@redhat.com> X-ClientProxiedBy: BL1PR13CA0265.namprd13.prod.outlook.com (2603:10b6:208:2ba::30) To MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-TrafficTypeDiagnostic: MN2PR12MB4783:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MN2PR12MB4192.namprd12.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230016)(4636009)(376002)(366004)(346002)(136003)(39860400002)(396003)(5660300002)(8936002)(7416002)(7406005)(33656002)(2906002)(478600001)(26005)(86362001)(6506007)(6512007)(6486002)(8676002)(107886003)(2616005)(1076003)(186003)(38100700002)(83380400001)(41300700001)(66556008)(6916009)(4326008)(54906003)(36756003)(66476007)(316002)(66946007); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?m5O4tfz8WmT8mit0zKYsuq1NArr8EDAaGnEAW75ZquZisT8K52BgYjwek6vo?= =?us-ascii?Q?R5vR9Q24ad4Thkc+b644rL1mlymfWiv3uGB/P9i5eddDBS+npuIH0H6K8x0p?= =?us-ascii?Q?Y4aBo8MbYxcytmqPkqEGtEqqDXL5li+V1a+xNXPqFgt9yYPE9EoVFYkfYcdj?= =?us-ascii?Q?Busv6FT12zAWSMgL3ryrWW6M9jEIp16pac68PJhuIexkTlITruPqzwlihuIG?= =?us-ascii?Q?94ifwlZppWwlvqMb77KEh/IoZytAaQJMBPSWSoZW2CwLZzrA2D6w6Ex98H3G?= =?us-ascii?Q?/7wb6O8PMcsKmBt3RV2svB6eN16FsMbFg6IHLDHY3Uxpn/m0BvgqHXcBaOB2?= =?us-ascii?Q?nlT0A92rijjEEoR81XRIeGSo26IDu4gDzDW7CWMwtiC5NryqFkVK/ea8Vjd7?= =?us-ascii?Q?MBvjGk3FELJC85Rh+vs3ccvQyk+olOetUhNnxZYV0qBtcnsn03UfazMt9mmu?= =?us-ascii?Q?j8Uye+7HYzwTeSjDZrn4bBN2WK7gVWO8rIfwdxHd5OVbA2i80FRrDUM0XOmF?= =?us-ascii?Q?84891zJs5nwVj1DzJno4El/JrluxCFUqHKZ3TiksaU9MSTNNqOkSiLhkv+ZH?= =?us-ascii?Q?la4i9P9ZPgIdVWgGBtJHT+pBZU8/JDs1bp+CkMuNSSQMCUyZsj1zS1I4vZYR?= =?us-ascii?Q?U6cuxCY+HcepkMMA556rU/3wS2LB7s/Idv0w17V9Cu1K5PectQ1j9ssVwHPj?= =?us-ascii?Q?cqamtNPopKkfQMmjY4LMVtd87rFhSB7rIhXIawp8k1H4W97hcIWw8SliWSbG?= =?us-ascii?Q?sQ8Nzu/HZfq98lpYV6t+2KfkeCtUhA8Sv4OGxXIvOR1JLpsNDa5QgthXjEMY?= =?us-ascii?Q?x95gleeci8S78HIDkmsRIFDbFZJXdKs24MdbwO2cxkWIQI5SNb99UcR4g0Ve?= =?us-ascii?Q?hubtUpMQ7+P94boHgJQxjzKeMSQgAD+POkDPWGIMmCJde77gm6l4JyqBnn9o?= =?us-ascii?Q?LtOTAkXLNPsQD+OGRiGll4TpFUuqEC1hFZq7wiqwcFtMYXvmE0cnD8yOSUxb?= =?us-ascii?Q?BPj4K/dSpEgIEyFnsYq98QddT0km3g0/MVUmzb4MCbs6xaQ5RWCdSZd0vEY3?= =?us-ascii?Q?rNWSVZVpt7hF/sfFZuSo8aY9a3/dhjUPYC2xYmS9gXl0mzdr+6n10lWOiLYG?= =?us-ascii?Q?kT/bYokelZM51R7VRQWW0sFZdbOCeUx/ONGeDEydMB+eca7mjKecPe8ofeRl?= =?us-ascii?Q?CX8J9vqB6xbpvdGKi3qKvOcn40/dnW+s5QQUNcsOXU5rovuq3r2drFFAnk8q?= =?us-ascii?Q?DlPrUZSeUPe91O3TY7QZRMOj/bwS4H6cwZbLZ7Y67Co3c2igEOzLCrcNsleA?= =?us-ascii?Q?s5L+XrBeNCnNuxaNB0t4uUCAYG1CxrhOPpNq8P1LlVp+yNQPj6od4hrGfKoF?= =?us-ascii?Q?3PVtA1BNHa1bAe4FryQK0l6jvF3qP2C1xD2KvaQ5ln5vU9M9kYSMNmtilEgb?= =?us-ascii?Q?ojdjr5PUhVJHK6vSxHXD0s/JkesS08/qjryWgk7IHPgkzS2qS4Y55MffYOR3?= =?us-ascii?Q?Iw9QlN4XkximTZuTTsS+2ZImVwQNvgXofpzQl+9tjtXMqwBOdgAkoPCyQerq?= =?us-ascii?Q?z2s1DjBByfthAT2on6Fm+gqEWIr7FjZyGU2ALPBL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2022 20:08:31.2135 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: e9MiieropZOiHFi/DBbO/QgDICEon2BdheESMjxTfFqHvMd2zqkxDJayXqLFJ76T X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4783 Subject: Re: [Intel-gfx] [PATCH v4 1/2] vfio: Replace the DMA unmapping notifier with a callback 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: kvm@vger.kernel.org, David Airlie , dri-devel@lists.freedesktop.org, Vineeth Vijayan , Alexander Gordeev , Christoph Hellwig , linux-s390@vger.kernel.org, Matthew Rosato , Halil Pasic , Nicolin Chen , Christian Borntraeger , intel-gfx@lists.freedesktop.org, Tony Krowiak , Eric Farman , Vasily Gorbik , Heiko Carstens , Harald Freudenberger , Rodrigo Vivi , intel-gvt-dev@lists.freedesktop.org, Jason Herne , Cornelia Huck , Peter Oberparleiter , Sven Schnelle Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Wed, Jul 20, 2022 at 01:41:13PM -0600, Alex Williamson wrote: > ie. we don't need the gfn, we only need the iova. Right, that makes sense > However then I start to wonder why we're passing in 1 for the number of > pages because this previously notifier, now callback is called for the > entire vfio_dma range when we find any pinned pages. Well, it is doing this because it only ever pins one page. The drivers are confused about what the contract is. vfio is calling the notifier with the entire IOVA range that is being unmapped and the drivers are expecting to receive notifications only for the IOVA they have actually pinned. > Should ap and ccw implementations of .dma_unmap just be replaced with a > BUG_ON(1)? The point of these callbacks is to halt concurrent DMA, and ccw does that today. It looks like AP is missing a call to ap_aqic(), so it is probably double wrong. What I'd suggest is adding a WARN_ON that the dma->pfn_list is not empty and leave these functions alone. Most likely AP should be fixed to call vfio_ap_irq_disable() and to check the q->saved_pfn against the IOVA. But I'm inclined to leave this as-is for this series given we are at rc7. Jason 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26406C433EF for ; Wed, 20 Jul 2022 20:08:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229756AbiGTUIf (ORCPT ); Wed, 20 Jul 2022 16:08:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229492AbiGTUIe (ORCPT ); Wed, 20 Jul 2022 16:08:34 -0400 Received: from NAM12-DM6-obe.outbound.protection.outlook.com (mail-dm6nam12on2065.outbound.protection.outlook.com [40.107.243.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 608AF4F6A6; Wed, 20 Jul 2022 13:08:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=h7Vv1tHoh8XNfOkcW2qPnQ2GhdNEKsYx3Gy6duOarqMG8rE4bksOR27aELOzoKTfWZh16ypW4JnvU2PNbXadN9XarkyvaVvb1OHqmyj5Lwvauh+vPXzZZlld7fHBBOJGNzIXY7704c+GX/V/0utRMPdgWzaUO4eXCJo9xsyad1DkD5oheOZQjFcMNOYbMoe90mBe2RIn+i7iq7xpye64iNWBiaZl2RHB2pSq7zgBbCy5AEE/brmr4EgyBCTD1Crjt5HeAHXSEk3hQoQ9KqB/Pi1xW6hOLdVJbybK8yHnRANomD2uTdx+p7AnlgHpTsQCJEhJewVgcMb/Oyn6zr9yaw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=b/zNR3VeaxC/rjRF1MXukl3kHZ1v8pua346nG+LKAjqvJ3rxeJuuIh3RvcYdFG9k7tuuZT9k9osrUrWExQtiJTy8L6hIt6gxabXn/hA8W1Y+K5iEJcDpI+3nRaO3rL/vSbsuBWIjPEy3hvd+RNKi0mAsK8XnFpkOU+8CmCCqWzGtqk58s6/12XeRkSr0/Clsres67AydM6b+0WapsD/qTBc+zDgPe0OYKxzR4NltKMm5ktwA/yCvsu2mHEntVcpLkTq2zo8ZAIMJsrMcFIpnYzVUXFcXLrC+V4Z2sPAHKtjLZgdMxEq8E4nxeA4eiFtS6Xu8rN87MPpaYCEFsyhDIw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=D8WjuBh6ZGgKl1mZndxxpKc84EJIpcI4CNnoJH47MrzIVXF+85zd5vdBwioiJiZ7VKFK7IS3FmmIX84Pu872+1BW65aFY2tr9tqaWFz7P+AQtCr37wvlp32KX0wD8AHKV0yZpeTM1JVyqL8ipkMXtXajaSU9UMPquIeANRZ5XAN8Cn/FaDAZGIRrI/mCFtWmJayYlwY1ReRym8MkCT5ghiCwC/A90Og35pZV5DMhN/4ouuFXywtJOxW9meykusznPJfqUBjkId/0KkmwRhrfZtNAuNgd6lltpfVPkdvKp06nY+qh53cvNfO34qFu8R9VlypHZo+eR6pZLUJ8RP9OrA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) by MN2PR12MB4783.namprd12.prod.outlook.com (2603:10b6:208:3e::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5438.21; Wed, 20 Jul 2022 20:08:31 +0000 Received: from MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb]) by MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb%3]) with mapi id 15.20.5458.018; Wed, 20 Jul 2022 20:08:31 +0000 Date: Wed, 20 Jul 2022 17:08:29 -0300 From: Jason Gunthorpe To: Alex Williamson Cc: Alexander Gordeev , David Airlie , Christian Borntraeger , Cornelia Huck , Daniel Vetter , dri-devel@lists.freedesktop.org, Harald Freudenberger , Vasily Gorbik , Heiko Carstens , intel-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, Jani Nikula , Jason Herne , Joonas Lahtinen , kvm@vger.kernel.org, linux-s390@vger.kernel.org, Matthew Rosato , Peter Oberparleiter , Halil Pasic , Rodrigo Vivi , Sven Schnelle , Tvrtko Ursulin , Vineeth Vijayan , Zhi Wang , Tony Krowiak , Eric Farman , Christoph Hellwig , Kevin Tian , Zhenyu Wang , Nicolin Chen Subject: Re: [PATCH v4 1/2] vfio: Replace the DMA unmapping notifier with a callback Message-ID: <20220720200829.GW4609@nvidia.com> References: <0-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <1-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <20220720134113.4225f9d6.alex.williamson@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220720134113.4225f9d6.alex.williamson@redhat.com> X-ClientProxiedBy: BL1PR13CA0265.namprd13.prod.outlook.com (2603:10b6:208:2ba::30) To MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-TrafficTypeDiagnostic: MN2PR12MB4783:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MN2PR12MB4192.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(4636009)(376002)(366004)(346002)(136003)(39860400002)(396003)(5660300002)(8936002)(7416002)(7406005)(33656002)(2906002)(478600001)(26005)(86362001)(6506007)(6512007)(6486002)(8676002)(107886003)(2616005)(1076003)(186003)(38100700002)(83380400001)(41300700001)(66556008)(6916009)(4326008)(54906003)(36756003)(66476007)(316002)(66946007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?m5O4tfz8WmT8mit0zKYsuq1NArr8EDAaGnEAW75ZquZisT8K52BgYjwek6vo?= =?us-ascii?Q?R5vR9Q24ad4Thkc+b644rL1mlymfWiv3uGB/P9i5eddDBS+npuIH0H6K8x0p?= =?us-ascii?Q?Y4aBo8MbYxcytmqPkqEGtEqqDXL5li+V1a+xNXPqFgt9yYPE9EoVFYkfYcdj?= =?us-ascii?Q?Busv6FT12zAWSMgL3ryrWW6M9jEIp16pac68PJhuIexkTlITruPqzwlihuIG?= =?us-ascii?Q?94ifwlZppWwlvqMb77KEh/IoZytAaQJMBPSWSoZW2CwLZzrA2D6w6Ex98H3G?= =?us-ascii?Q?/7wb6O8PMcsKmBt3RV2svB6eN16FsMbFg6IHLDHY3Uxpn/m0BvgqHXcBaOB2?= =?us-ascii?Q?nlT0A92rijjEEoR81XRIeGSo26IDu4gDzDW7CWMwtiC5NryqFkVK/ea8Vjd7?= =?us-ascii?Q?MBvjGk3FELJC85Rh+vs3ccvQyk+olOetUhNnxZYV0qBtcnsn03UfazMt9mmu?= =?us-ascii?Q?j8Uye+7HYzwTeSjDZrn4bBN2WK7gVWO8rIfwdxHd5OVbA2i80FRrDUM0XOmF?= =?us-ascii?Q?84891zJs5nwVj1DzJno4El/JrluxCFUqHKZ3TiksaU9MSTNNqOkSiLhkv+ZH?= =?us-ascii?Q?la4i9P9ZPgIdVWgGBtJHT+pBZU8/JDs1bp+CkMuNSSQMCUyZsj1zS1I4vZYR?= =?us-ascii?Q?U6cuxCY+HcepkMMA556rU/3wS2LB7s/Idv0w17V9Cu1K5PectQ1j9ssVwHPj?= =?us-ascii?Q?cqamtNPopKkfQMmjY4LMVtd87rFhSB7rIhXIawp8k1H4W97hcIWw8SliWSbG?= =?us-ascii?Q?sQ8Nzu/HZfq98lpYV6t+2KfkeCtUhA8Sv4OGxXIvOR1JLpsNDa5QgthXjEMY?= =?us-ascii?Q?x95gleeci8S78HIDkmsRIFDbFZJXdKs24MdbwO2cxkWIQI5SNb99UcR4g0Ve?= =?us-ascii?Q?hubtUpMQ7+P94boHgJQxjzKeMSQgAD+POkDPWGIMmCJde77gm6l4JyqBnn9o?= =?us-ascii?Q?LtOTAkXLNPsQD+OGRiGll4TpFUuqEC1hFZq7wiqwcFtMYXvmE0cnD8yOSUxb?= =?us-ascii?Q?BPj4K/dSpEgIEyFnsYq98QddT0km3g0/MVUmzb4MCbs6xaQ5RWCdSZd0vEY3?= =?us-ascii?Q?rNWSVZVpt7hF/sfFZuSo8aY9a3/dhjUPYC2xYmS9gXl0mzdr+6n10lWOiLYG?= =?us-ascii?Q?kT/bYokelZM51R7VRQWW0sFZdbOCeUx/ONGeDEydMB+eca7mjKecPe8ofeRl?= =?us-ascii?Q?CX8J9vqB6xbpvdGKi3qKvOcn40/dnW+s5QQUNcsOXU5rovuq3r2drFFAnk8q?= =?us-ascii?Q?DlPrUZSeUPe91O3TY7QZRMOj/bwS4H6cwZbLZ7Y67Co3c2igEOzLCrcNsleA?= =?us-ascii?Q?s5L+XrBeNCnNuxaNB0t4uUCAYG1CxrhOPpNq8P1LlVp+yNQPj6od4hrGfKoF?= =?us-ascii?Q?3PVtA1BNHa1bAe4FryQK0l6jvF3qP2C1xD2KvaQ5ln5vU9M9kYSMNmtilEgb?= =?us-ascii?Q?ojdjr5PUhVJHK6vSxHXD0s/JkesS08/qjryWgk7IHPgkzS2qS4Y55MffYOR3?= =?us-ascii?Q?Iw9QlN4XkximTZuTTsS+2ZImVwQNvgXofpzQl+9tjtXMqwBOdgAkoPCyQerq?= =?us-ascii?Q?z2s1DjBByfthAT2on6Fm+gqEWIr7FjZyGU2ALPBL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2022 20:08:31.2135 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: e9MiieropZOiHFi/DBbO/QgDICEon2BdheESMjxTfFqHvMd2zqkxDJayXqLFJ76T X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4783 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Wed, Jul 20, 2022 at 01:41:13PM -0600, Alex Williamson wrote: > ie. we don't need the gfn, we only need the iova. Right, that makes sense > However then I start to wonder why we're passing in 1 for the number of > pages because this previously notifier, now callback is called for the > entire vfio_dma range when we find any pinned pages. Well, it is doing this because it only ever pins one page. The drivers are confused about what the contract is. vfio is calling the notifier with the entire IOVA range that is being unmapped and the drivers are expecting to receive notifications only for the IOVA they have actually pinned. > Should ap and ccw implementations of .dma_unmap just be replaced with a > BUG_ON(1)? The point of these callbacks is to halt concurrent DMA, and ccw does that today. It looks like AP is missing a call to ap_aqic(), so it is probably double wrong. What I'd suggest is adding a WARN_ON that the dma->pfn_list is not empty and leave these functions alone. Most likely AP should be fixed to call vfio_ap_irq_disable() and to check the q->saved_pfn against the IOVA. But I'm inclined to leave this as-is for this series given we are at rc7. Jason 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id CC723CCA486 for ; Wed, 20 Jul 2022 20:08:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A849E11BA26; Wed, 20 Jul 2022 20:08:35 +0000 (UTC) Received: from NAM12-DM6-obe.outbound.protection.outlook.com (mail-dm6nam12on2071.outbound.protection.outlook.com [40.107.243.71]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6D0BB11B4E3; Wed, 20 Jul 2022 20:08:34 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=h7Vv1tHoh8XNfOkcW2qPnQ2GhdNEKsYx3Gy6duOarqMG8rE4bksOR27aELOzoKTfWZh16ypW4JnvU2PNbXadN9XarkyvaVvb1OHqmyj5Lwvauh+vPXzZZlld7fHBBOJGNzIXY7704c+GX/V/0utRMPdgWzaUO4eXCJo9xsyad1DkD5oheOZQjFcMNOYbMoe90mBe2RIn+i7iq7xpye64iNWBiaZl2RHB2pSq7zgBbCy5AEE/brmr4EgyBCTD1Crjt5HeAHXSEk3hQoQ9KqB/Pi1xW6hOLdVJbybK8yHnRANomD2uTdx+p7AnlgHpTsQCJEhJewVgcMb/Oyn6zr9yaw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=b/zNR3VeaxC/rjRF1MXukl3kHZ1v8pua346nG+LKAjqvJ3rxeJuuIh3RvcYdFG9k7tuuZT9k9osrUrWExQtiJTy8L6hIt6gxabXn/hA8W1Y+K5iEJcDpI+3nRaO3rL/vSbsuBWIjPEy3hvd+RNKi0mAsK8XnFpkOU+8CmCCqWzGtqk58s6/12XeRkSr0/Clsres67AydM6b+0WapsD/qTBc+zDgPe0OYKxzR4NltKMm5ktwA/yCvsu2mHEntVcpLkTq2zo8ZAIMJsrMcFIpnYzVUXFcXLrC+V4Z2sPAHKtjLZgdMxEq8E4nxeA4eiFtS6Xu8rN87MPpaYCEFsyhDIw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=uFIV/uobVcUsxlqWI/QapcqAfKZu+w2VoltTiRmWEuU=; b=D8WjuBh6ZGgKl1mZndxxpKc84EJIpcI4CNnoJH47MrzIVXF+85zd5vdBwioiJiZ7VKFK7IS3FmmIX84Pu872+1BW65aFY2tr9tqaWFz7P+AQtCr37wvlp32KX0wD8AHKV0yZpeTM1JVyqL8ipkMXtXajaSU9UMPquIeANRZ5XAN8Cn/FaDAZGIRrI/mCFtWmJayYlwY1ReRym8MkCT5ghiCwC/A90Og35pZV5DMhN/4ouuFXywtJOxW9meykusznPJfqUBjkId/0KkmwRhrfZtNAuNgd6lltpfVPkdvKp06nY+qh53cvNfO34qFu8R9VlypHZo+eR6pZLUJ8RP9OrA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) by MN2PR12MB4783.namprd12.prod.outlook.com (2603:10b6:208:3e::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5438.21; Wed, 20 Jul 2022 20:08:31 +0000 Received: from MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb]) by MN2PR12MB4192.namprd12.prod.outlook.com ([fe80::ac35:7c4b:3282:abfb%3]) with mapi id 15.20.5458.018; Wed, 20 Jul 2022 20:08:31 +0000 Date: Wed, 20 Jul 2022 17:08:29 -0300 From: Jason Gunthorpe To: Alex Williamson Subject: Re: [PATCH v4 1/2] vfio: Replace the DMA unmapping notifier with a callback Message-ID: <20220720200829.GW4609@nvidia.com> References: <0-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <1-v4-681e038e30fd+78-vfio_unmap_notif_jgg@nvidia.com> <20220720134113.4225f9d6.alex.williamson@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220720134113.4225f9d6.alex.williamson@redhat.com> X-ClientProxiedBy: BL1PR13CA0265.namprd13.prod.outlook.com (2603:10b6:208:2ba::30) To MN2PR12MB4192.namprd12.prod.outlook.com (2603:10b6:208:1d5::15) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-TrafficTypeDiagnostic: MN2PR12MB4783:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MN2PR12MB4192.namprd12.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230016)(4636009)(376002)(366004)(346002)(136003)(39860400002)(396003)(5660300002)(8936002)(7416002)(7406005)(33656002)(2906002)(478600001)(26005)(86362001)(6506007)(6512007)(6486002)(8676002)(107886003)(2616005)(1076003)(186003)(38100700002)(83380400001)(41300700001)(66556008)(6916009)(4326008)(54906003)(36756003)(66476007)(316002)(66946007); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?m5O4tfz8WmT8mit0zKYsuq1NArr8EDAaGnEAW75ZquZisT8K52BgYjwek6vo?= =?us-ascii?Q?R5vR9Q24ad4Thkc+b644rL1mlymfWiv3uGB/P9i5eddDBS+npuIH0H6K8x0p?= =?us-ascii?Q?Y4aBo8MbYxcytmqPkqEGtEqqDXL5li+V1a+xNXPqFgt9yYPE9EoVFYkfYcdj?= =?us-ascii?Q?Busv6FT12zAWSMgL3ryrWW6M9jEIp16pac68PJhuIexkTlITruPqzwlihuIG?= =?us-ascii?Q?94ifwlZppWwlvqMb77KEh/IoZytAaQJMBPSWSoZW2CwLZzrA2D6w6Ex98H3G?= =?us-ascii?Q?/7wb6O8PMcsKmBt3RV2svB6eN16FsMbFg6IHLDHY3Uxpn/m0BvgqHXcBaOB2?= =?us-ascii?Q?nlT0A92rijjEEoR81XRIeGSo26IDu4gDzDW7CWMwtiC5NryqFkVK/ea8Vjd7?= =?us-ascii?Q?MBvjGk3FELJC85Rh+vs3ccvQyk+olOetUhNnxZYV0qBtcnsn03UfazMt9mmu?= =?us-ascii?Q?j8Uye+7HYzwTeSjDZrn4bBN2WK7gVWO8rIfwdxHd5OVbA2i80FRrDUM0XOmF?= =?us-ascii?Q?84891zJs5nwVj1DzJno4El/JrluxCFUqHKZ3TiksaU9MSTNNqOkSiLhkv+ZH?= =?us-ascii?Q?la4i9P9ZPgIdVWgGBtJHT+pBZU8/JDs1bp+CkMuNSSQMCUyZsj1zS1I4vZYR?= =?us-ascii?Q?U6cuxCY+HcepkMMA556rU/3wS2LB7s/Idv0w17V9Cu1K5PectQ1j9ssVwHPj?= =?us-ascii?Q?cqamtNPopKkfQMmjY4LMVtd87rFhSB7rIhXIawp8k1H4W97hcIWw8SliWSbG?= =?us-ascii?Q?sQ8Nzu/HZfq98lpYV6t+2KfkeCtUhA8Sv4OGxXIvOR1JLpsNDa5QgthXjEMY?= =?us-ascii?Q?x95gleeci8S78HIDkmsRIFDbFZJXdKs24MdbwO2cxkWIQI5SNb99UcR4g0Ve?= =?us-ascii?Q?hubtUpMQ7+P94boHgJQxjzKeMSQgAD+POkDPWGIMmCJde77gm6l4JyqBnn9o?= =?us-ascii?Q?LtOTAkXLNPsQD+OGRiGll4TpFUuqEC1hFZq7wiqwcFtMYXvmE0cnD8yOSUxb?= =?us-ascii?Q?BPj4K/dSpEgIEyFnsYq98QddT0km3g0/MVUmzb4MCbs6xaQ5RWCdSZd0vEY3?= =?us-ascii?Q?rNWSVZVpt7hF/sfFZuSo8aY9a3/dhjUPYC2xYmS9gXl0mzdr+6n10lWOiLYG?= =?us-ascii?Q?kT/bYokelZM51R7VRQWW0sFZdbOCeUx/ONGeDEydMB+eca7mjKecPe8ofeRl?= =?us-ascii?Q?CX8J9vqB6xbpvdGKi3qKvOcn40/dnW+s5QQUNcsOXU5rovuq3r2drFFAnk8q?= =?us-ascii?Q?DlPrUZSeUPe91O3TY7QZRMOj/bwS4H6cwZbLZ7Y67Co3c2igEOzLCrcNsleA?= =?us-ascii?Q?s5L+XrBeNCnNuxaNB0t4uUCAYG1CxrhOPpNq8P1LlVp+yNQPj6od4hrGfKoF?= =?us-ascii?Q?3PVtA1BNHa1bAe4FryQK0l6jvF3qP2C1xD2KvaQ5ln5vU9M9kYSMNmtilEgb?= =?us-ascii?Q?ojdjr5PUhVJHK6vSxHXD0s/JkesS08/qjryWgk7IHPgkzS2qS4Y55MffYOR3?= =?us-ascii?Q?Iw9QlN4XkximTZuTTsS+2ZImVwQNvgXofpzQl+9tjtXMqwBOdgAkoPCyQerq?= =?us-ascii?Q?z2s1DjBByfthAT2on6Fm+gqEWIr7FjZyGU2ALPBL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 63e8c680-5a38-4349-e819-08da6a8b9e08 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2022 20:08:31.2135 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: e9MiieropZOiHFi/DBbO/QgDICEon2BdheESMjxTfFqHvMd2zqkxDJayXqLFJ76T X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4783 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: kvm@vger.kernel.org, David Airlie , Kevin Tian , dri-devel@lists.freedesktop.org, Vineeth Vijayan , Alexander Gordeev , Christoph Hellwig , linux-s390@vger.kernel.org, Matthew Rosato , Halil Pasic , Nicolin Chen , Christian Borntraeger , intel-gfx@lists.freedesktop.org, Zhi Wang , Tony Krowiak , Eric Farman , Vasily Gorbik , Heiko Carstens , Harald Freudenberger , Rodrigo Vivi , intel-gvt-dev@lists.freedesktop.org, Jason Herne , Tvrtko Ursulin , Cornelia Huck , Peter Oberparleiter , Sven Schnelle Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Wed, Jul 20, 2022 at 01:41:13PM -0600, Alex Williamson wrote: > ie. we don't need the gfn, we only need the iova. Right, that makes sense > However then I start to wonder why we're passing in 1 for the number of > pages because this previously notifier, now callback is called for the > entire vfio_dma range when we find any pinned pages. Well, it is doing this because it only ever pins one page. The drivers are confused about what the contract is. vfio is calling the notifier with the entire IOVA range that is being unmapped and the drivers are expecting to receive notifications only for the IOVA they have actually pinned. > Should ap and ccw implementations of .dma_unmap just be replaced with a > BUG_ON(1)? The point of these callbacks is to halt concurrent DMA, and ccw does that today. It looks like AP is missing a call to ap_aqic(), so it is probably double wrong. What I'd suggest is adding a WARN_ON that the dma->pfn_list is not empty and leave these functions alone. Most likely AP should be fixed to call vfio_ap_irq_disable() and to check the q->saved_pfn against the IOVA. But I'm inclined to leave this as-is for this series given we are at rc7. Jason