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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 7BC30CCA464 for ; Thu, 15 Oct 2026 19:52:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:CC:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ztYwySdM4uRqQRo31SKMlEzFr1RxXsgSUksHxjNlqMA=; b=3ranM9xe9lcTcy G68AOR8kGa3EWYYtkach5loxrgaYqGQBElbGQTZ15AeIaEvp0MHieX+h7hRJ43Jbef2cWviYkAOF7 c1uaRjmus9AKSAQoicX7NZwAdMba09etMrBe/0piKuUbxRTEDTWYZrzOPrl9F8juZBS+R7rYTHB6S u4w+5xaUthJGij6eLjO2NMYnbUpuM0enIA05+EpaIuXUGPLbmI/OluiM7n9LGaiAGOAQxGiQrxEq2 SP8PkEZW9s7BzAYKpA/D9nXt3Ux0Y/ZAWjUAtN3GPz4AlY2Fq8apO1OZBZxeP5YC3McsfIM7MMdAx yy+olNI551QUdYZR19vw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xHRUm-00000001HGo-0GOx; Thu, 15 Oct 2026 19:52:08 +0000 Received: from mail-eastus2azlp170100001.outbound.protection.outlook.com ([2a01:111:f403:c110::1] helo=BN1PR04CU002.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xHRUj-00000001HGP-1LwP for linux-riscv@lists.infradead.org; Thu, 15 Oct 2026 19:52:06 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=e7PrZW/jkQ3yueafGe5kKcw86yKgPfBKEyvvRkFjN3ERAbewytVy1BTpgUnMnEnDw2l53Yiu92hqD1hhA7AaDQI8cxJ33jS740Ht8gkANmVD1pu7aLsKEC550cyGuDHmxb5vrOINf6KKrrLBLMJlM7pQQgFDON0HiQ1VXc2ZcfXAuu7M5N8MqRsd1wpXtOdFKBSiQGGDwhLvVMplj1ZxOPUtgpELSsTyWC8YCOSDeCMQlJYoOFBjonaMeRVVZRvi3a92uS1/2CUWLLrB1K3LB3Tkhxh9KPtybBLvmw0OnFr8ZCg3ZwNBIDRQb/5/bzNGUiKD2EJjw7Ilw1gyvLFOZA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=BGf4sBQCDOniHWBZJ+6LZ0pt+MAyBNBD+iLIotP4uas=; b=jdNPglfbCNAALQussjX7T8+VDMkXgsH948JnCHn29eOFdI6VtZvPBvCx/1dTsBtcGeRVVvjsNgY1qdGX5k6VrVjdb7jn5nWJC8P59fMAMQ5noSujlNvoTudArtjaBGQWOMJUzWpxZl8+71tibBA+NMbaiXN/j4kzUnrglLz+vL9syjOtfVGhmDeQBRnCl71/HhMayI3DU2GsjI1+1NnJukZATaTh6FdQXYPiBjsTSubzq24Jf1AWye54pd8WyCJMGtaj0OlbyhySLefYS+TyaX+KnjQ+IkVu8zRAseHyM1lOlEEjt+VGdXA+v+m+aNpblec6TqDD1MOXbhANI5e5rg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.117.160) smtp.rcpttodomain=kernel.org smtp.mailfrom=nvidia.com; dmarc=pass (p=reject sp=reject pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none (0) 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=BGf4sBQCDOniHWBZJ+6LZ0pt+MAyBNBD+iLIotP4uas=; b=peaNShgd+Y9HwYw3tEWdkal/hFNAjlQL9FTaM7iY5ytbSPXfVm7hWmvQ+lNYjWFGIXQBi0YnuLszNFgi4DinIb8Y9a7EeCZfaBKtogCRZxuYztJl0t9Kn3+YURCWGpznREhuoHlMm3a43xyb5THLHMknZFuPphrHZTeTFSdDSGmzOuiboSpeuWIopXneqbvJX7jpNRYED7XyBd7cb9lnrDrPYdloPGA2rtGWH9uLZUXWUZzxgwzXtAgonvurz39nX3juZkVQTB8tXtqfDzP5Qtwj64sWsEyeUoj/b66nB7QCHvZHepv463O13hOQUW7UjUSmRdW0rtMiJ+Ykdwu/Sg== Received: from BN9PR03CA0468.namprd03.prod.outlook.com (2603:10b6:408:139::23) by IA3PR12MB570242.namprd12.prod.outlook.com (2603:10b6:208:715::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.522.14; Thu, 15 Oct 2026 19:52:00 +0000 Received: from BL02EPF0002992D.namprd02.prod.outlook.com (2603:10b6:408:139:cafe::9a) by BN9PR03CA0468.outlook.office365.com (2603:10b6:408:139::23) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.21.472.20 via Frontend Transport; Thu, 15 Oct 2026 19:52:00 +0000 X-MS-Exchange-Authentication-Results: mx.microsoft.com 1; spf=pass (sender IP is 216.228.117.160) smtp.mailfrom=nvidia.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.117.160 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C Received: from mail.nvidia.com (216.228.117.160) by BL02EPF0002992D.mail.protection.outlook.com (10.167.249.58) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.522.6 via Frontend Transport; Thu, 15 Oct 2026 19:52:00 +0000 Received: from rnnvmail204.nvidia.com (10.129.68.6) by mail.nvidia.com (10.129.200.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.56; Thu, 15 Oct 2026 12:51:38 -0700 Received: from rnnvmail203.nvidia.com (10.129.68.9) by rnnvmail204.nvidia.com (10.129.68.6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49; Thu, 15 Oct 2026 12:51:37 -0700 Received: from nvidia.com (10.127.8.13) by mail.nvidia.com (10.129.68.9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.49 via Frontend Transport; Thu, 15 Oct 2026 12:51:35 -0700 Date: Thu, 15 Oct 2026 12:51:33 -0700 From: Nicolin Chen To: Jason Gunthorpe CC: Andrew Jones , , , , , , , , , , , , , , , Subject: Re: [PATCH v6 09/16] iommu/riscv: Reserve an MSI IOVA window for iommufd Message-ID: References: <20260925151659.419512-1-andrew.jones@oss.qualcomm.com> <20260925151659.419512-10-andrew.jones@oss.qualcomm.com> <179209292716.4133959.2758345963634439485.b4-review@b4> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <179209292716.4133959.2758345963634439485.b4-review@b4> X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL02EPF0002992D:EE_|IA3PR12MB570242:EE_ X-MS-Office365-Filtering-Correlation-Id: c32e24a8-5632-450c-768e-08df2af5c712 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|36860700016|23010399003|376014|1800799024|7416014|22082099003|10067099003|18002099003|11063799006|260925021911599003|260925022911599003|260925021311599003|4143699003|56012099006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230040)(82310400026)(36860700016)(23010399003)(376014)(1800799024)(7416014)(22082099003)(10067099003)(18002099003)(11063799006)(260925021911599003)(260925022911599003)(260925021311599003)(4143699003)(56012099006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: ZwXJgfz8qoWHJlNnCCHR6w9D1V92jYNHlSen9HQryYkeNm412nbKRDjgVoZ6DDgIUT5nCnxfLUnyXCOwQUAeSLZfXaxzOjlEfgU339N/b+zgThprxN4xy2bRO4JTEc8bqx3b5ECGro91XbwaEVv71tQYlRNA2/bEiq0hKrUMIa1/n2IyGaEneYWbLZH70zGKZKHJKqw60CCOMKIDh8EMHIDu/5jGfof3H0fHPNla2E7nlu0bMVy1qSlxN/Hkl9vYQ+/HX8cBKtARO5y2HqZZM/VdigmZUV9eO2Dx7X0WeqsmpQCMgRIlNjNPDcMlvva8ZI0Ns3W8vHppkiGYv2a2AYkWWBSoVepvAfGobrTSrbVu6ZifaZLje6U816dDRsczS1/mW6ktjTZWV2MBieng5WbCAIFOoYq990AmzpOLJTbG/meb3PSorx0XbIkFR7bd X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Oct 2026 19:52:00.3278 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c32e24a8-5632-450c-768e-08df2af5c712 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BL02EPF0002992D.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA3PR12MB570242 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261015_125205_393073_ACE17CF5 X-CRM114-Status: GOOD ( 13.38 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Thu, Oct 15, 2026 at 04:35:27PM -0300, Jason Gunthorpe wrote: > > Reserve one page per possible CPU, sufficient for each supervisor IMSIC > > page. Use a 16 MiB base instead of the 128 MiB convention used by ARM > > SMMU. kvmtool places its guest IMSIC at 128 MiB, so with IRQ bypass the > > domain-wide guest MSI address match can also capture host-delivered > > MSI writes to the SW MSI window and misdeliver them to the guest. > > > > 16 MiB falls in a hole in the current kvmtool and QEMU virt memory maps, > > away from their guest IMSIC windows and RAM. Keep the window below > > 4 GiB so devices with 32-bit MSI address registers can use it. > > And this is a good reason you should not follow ARM down this mad > road. Nicolin had some patches to allow userspace to select the SW_MSI > range instead of using a kernel hard coded value, which becomes a > sneaky ABI. It would be much better if riscv starts off on the right > foot instead of continuing this mistake. It was paused due to lack of an immediate interest: https://lore.kernel.org/linux-iommu/cover.1760487869.git.nicolinc@nvidia.com/ If riscv wants it, maybe we can give a push. Nicolin _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv