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 6D024FD5F8E for ; Wed, 8 Apr 2026 08:43:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version: Content-Transfer-Encoding:Content-Type:In-Reply-To:From:References:Cc:To: Subject:Date:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VbcQxoDZhnjIgU3TmyOsDbuwnwPpBv/1SzTcDEi1Rms=; b=VVgRV3wZLriR7Vq1JNgzmnuzWt Qd5+farcpVtDC34TQho71LxtXbFw/IOc7hRQeHHFeS1LJXMl8KpGp5RgwwaMF9f2tnJiL7faoGidI FbI/BUEgpiBJpHL85DS6rMUs2zUvvadU+d5m2H2CcC/tZAGyTEdmrJ0/kuATCj4Cn3e7CDSa7cMXU 3PPhakbj1nVZV5IWaSCo3Mrl6KartJ3TEsclsPs/vQtNFgmANfaQ4SdgnxIYBSjxOR+zzaasnvx3C mYu3uvcGFSAw+N6RK6ADAElZN+q0ehrLl6fycUmgI02sdJrBBBd+KLkD0C7/eUuTrjda//6XwzvDV HMn1O9Fw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wAOVL-00000008XJJ-1Kv3; Wed, 08 Apr 2026 08:43:19 +0000 Received: from mail-westus2azon11010025.outbound.protection.outlook.com ([52.101.46.25] helo=CO1PR03CU002.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wAOVI-00000008XIq-1Wf1; Wed, 08 Apr 2026 08:43:18 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=W3zVg1NDYapL7Ctf5LnzzSuw0Z3GO5k3zkX84R5FSGLSsIysLuLHWGn/3X07o0D4s4WOQXWAWv1zMODGKji5ACC1Bs2M0d07RugbX1td5JuVrE6pMAuHncnK/Wn++XE4jActjSDT1eS2U8OqQ3fdudUuj2sw1Cozcw4LVcAM0Tr3vI04vJNwJdTOTYEybzZqV5IrYFLnBuqfvGaaiYsHuVqKuBx/gXsiTKUi2Zc1yJ5GyCEDDyl6Azk7PTQzFsi6jImZdtDVvzfu/JxZdIixwr6kvijCUk4FdzpWSiNT+6bUW7kxSv08Bn/Psb96ZdbIer0VPg4Qj5K+fEB1ZRyGVA== 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=VbcQxoDZhnjIgU3TmyOsDbuwnwPpBv/1SzTcDEi1Rms=; b=aRLYM38MH6taI8gvPM9RTzr0baqlY9/RDGXesxQcmRe2ao1X5bMiIXthKy1GqnJ4HYTG8QqZwrxyeCCiL3gylfIVDdpCl5XE/YS8cYDvYFPOWi31pdXodWzvJ87/ClsvrKiAX2eJQZK9+STerIvPAlQfKg+FO4l9FbUb5vYpAGUH3s0nlSQ2vpYEtp7VfZCcDVQn5RBfmHD7LrCQJ9CPrXrb66RHoX2k9xhsRXhUbFurUOZooaITNhrolb3iBXkVJOxyq7IMp65KYEzMJIT2kNuD//kGFq2TgIXpLYaVLL71UI09/CUm7ONc7XqnJaQEyOrf/7NlSEceXJ1Nu2uNZQ== 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=VbcQxoDZhnjIgU3TmyOsDbuwnwPpBv/1SzTcDEi1Rms=; b=OnTOzqHsYmSd0FupfQgy39sW3Y88Ta82drOqmgV7Te6mmKESBMSiP0/Y7Xuu9HGvUjzN+hxw6hDGYoNSCQVXpn1Q+RNJj697ZJyaid8QOSWNA9EFtNEATcvANi8eI3WWgrrZym51XkVAzM+yKi/WRggm3Vk+0t7gAmpWj/gUY+/YhUF6Hyw3SGHqFnbCq8lng+c2rhYEaDDLO+hjoiWlrJOayEmvESs6p+jRCYnwSoZuzLJ8Itg4ouQ06RW7tyknmqrhTb8jv/0xHfOc5twuSFjnx7paWwSuXdQZNi1/fMCyEGFKahcq51nJPiswoORnVqigr29Bp575iMuVnynudw== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from DS2PR12MB9750.namprd12.prod.outlook.com (2603:10b6:8:2b0::12) by PH8PR12MB6892.namprd12.prod.outlook.com (2603:10b6:510:1bc::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9769.20; Wed, 8 Apr 2026 08:43:09 +0000 Received: from DS2PR12MB9750.namprd12.prod.outlook.com ([fe80::56a8:d6bf:e24c:b391]) by DS2PR12MB9750.namprd12.prod.outlook.com ([fe80::56a8:d6bf:e24c:b391%6]) with mapi id 15.20.9769.016; Wed, 8 Apr 2026 08:43:08 +0000 Message-ID: <94576121-d4ff-47fd-9ff8-2a00ff4c5c2a@nvidia.com> Date: Wed, 8 Apr 2026 09:42:54 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] iommu: Always fill in gather when unmapping To: Jason Gunthorpe , Robin Murphy Cc: Alexandre Ghiti , AngeloGioacchino Del Regno , Albert Ou , asahi@lists.linux.dev, Baolin Wang , iommu@lists.linux.dev, Janne Grunau , Jernej Skrabec , Joerg Roedel , Jean-Philippe Brucker , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-riscv@lists.infradead.org, linux-sunxi@lists.linux.dev, Matthias Brugger , Neal Gompa , Orson Zhai , Palmer Dabbelt , Paul Walmsley , Samuel Holland , Sven Peter , virtualization@lists.linux.dev, Chen-Yu Tsai , Will Deacon , Yong Wu , Chunyan Zhang , Lu Baolu , Janusz Krzysztofik , Joerg Roedel , patches@lists.linux.dev, Samiullah Khawaja , stable@vger.kernel.org, Vasant Hegde , "linux-tegra@vger.kernel.org" References: <0-v1-664d3acaabb9+78b-iommu_gather_always_jgg@nvidia.com> <20260401173650.GD310919@nvidia.com> <20260402225121.GI310919@nvidia.com> From: Jon Hunter Content-Language: en-US In-Reply-To: <20260402225121.GI310919@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: LO4P123CA0002.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:150::7) To DS2PR12MB9750.namprd12.prod.outlook.com (2603:10b6:8:2b0::12) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS2PR12MB9750:EE_|PH8PR12MB6892:EE_ X-MS-Office365-Filtering-Correlation-Id: 399663cc-b8aa-4c0f-7c70-08de954adc10 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|10070799003|7416014|376014|18002099003|56012099003|22082099003; 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:DS2PR12MB9750.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(10070799003)(7416014)(376014)(18002099003)(56012099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 2 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?eU13MTZXbzdidVgrTzJGNDV0WHJNZFZqQzMwM2FMSUltMGNmWWFsSElyNU81?= =?utf-8?B?Mml6NzVaY1FXQmdpb0JaeFRHTE9SUmMzcGpFVi9tYmxaMUVScDVsWXovaW5x?= =?utf-8?B?OHIxbGVYdHFyU2oxbmI2WGRGQmdKenJKbExzMUNqMlBjZDZBZVkyTWc3aUI1?= =?utf-8?B?dEJHcGhCRTZ1eCswRFE5Uk1XL2hNK0Y1MXNJanNLY3ZiOHppUnY2Zkw1SGE1?= =?utf-8?B?MEswaTBTWDdEMGFiVXhVY1ZNQkNCWExjQUNpejQvZEYvNGk4OE5jd0xqMGFO?= =?utf-8?B?NlBWa2dJNUp5dC9oZVRsazQwcjVlL1Ryb2hHMDhRMXYzS2taL25LbUhSNjU4?= =?utf-8?B?elNSNVVLMXlGd05ybm1wSThCNlJFdFp6cVZjMzFIWDVxMStFMkhNU1phZ3JS?= =?utf-8?B?Z3poVG9pSmhwL3JZeCtDUWcyTEhmSlVUdWRaUWxIQlQ3MmViWGFOK1JmeWFO?= =?utf-8?B?akR0a1R5c3VyTzVOc1IwL2RLV1FyU3plMHpHM3l2cnRPQmdyMFpZMDczNzZN?= =?utf-8?B?R3ZlRVhuU1JkL3RyRGlMUkdmbWx2ZDFjK2dSVmUxVlQ1bnZISDRibloydmgw?= =?utf-8?B?WTBTQTVSVWUyYmJDck8xM0xsSzhqalM3Y29qdXF5ZVZwWko4N3pkTTh5aGhq?= =?utf-8?B?dE9HTUY2VXFVVmV6YjZ4STg5Z1psQW1SbG1XNkJ3UURjc2VGRjF0QjlsSEgr?= =?utf-8?B?Z1VpM1FBcGQ0K002Zk1VS0JSMk84QlFlVjJhMW13OXdGYXZYaGw4NEJQMnRF?= =?utf-8?B?L2xhcUlUcXBZN3FyMEV4YnFuZWdoY2xkUEZrUTV2Mmszek8xS0J3QlZNNlRx?= =?utf-8?B?YzBLdWZZeTVKSnJyTzFlZkJjcmo4L1dDWkNhL0dnbDU1UXZyeENhZ3hmc2RB?= =?utf-8?B?ZUFqNVNMQ2JtalMxZEtTTnNpUWlIOXJ2N1FEZXRCUEg3cXAvWWlsVWx0VGxt?= =?utf-8?B?Z3FlT3dvMzU2T0V6WWtZbHN0Z1lqMjJKYUNtZDFXVzF2TFFWa2hZNjlibHpR?= =?utf-8?B?N0prV1llTzBqczJBeDFSdkM0b1ZNUEw2NzF0YkozVHNOUitsZm5lVEJTTTdZ?= =?utf-8?B?M041eXFQUE9raFF6U2U4dDdBb1NuK1AwWFBBOENXQXp5MklCaERzME50TVBo?= =?utf-8?B?THRSbEFCdWRtbmFkQWN6ZFJoOGxDaHVRcHg3WGNKOGVUWG5xblR5VTdHRnZG?= =?utf-8?B?ZUg2a2Fqb0Vzb0tVNDZkc2ZXbk9zWmdDMXk3S215UGYzaTVyamdNNkJHTHVv?= =?utf-8?B?MU1wRFhKdVNGZmQwLzZ2Yzc1OTRibVhCaE54UFVwWTVCejAzbE5HR2ZoQXYv?= =?utf-8?B?RjFQVGp4MFc3QnRvN2w3RENXSEgvZ1Izc3h3OEltRWJPV3hER0ZuZmVOekt6?= =?utf-8?B?bVF2L01pdUhhL0g5S3NKV3RMQm1CdWxYMGJBbE4vSUZWTm1odXk1YnBVRUJo?= =?utf-8?B?L3cwWEd1OFBUSFN2Yi94U2lDbUhyUmpQQ1hDWWJXWC9xOVY4VHdMQ3NPa3Vy?= =?utf-8?B?Q1JKdkxJTWtYbHAvdTF3SVd6U2lZWVExaWhhOE1vY1hsVXdhU28waHROT0l4?= =?utf-8?B?WFcyK0JPbHZwZUxJYytrQ1FjMnZJOVViMmNDR1hndnR2V1EzSUQ1UVA0K3dB?= =?utf-8?B?S2gzbkVmQ3JscjZGNktaUlFaM1FLM1dVbnptVEhHcTlmQ1dGZlBqQm9jWWRO?= =?utf-8?B?bjQxOHJmTmdnY2ZPNXN5SkNUWk40Z2YwMDlaZkJXL01EbFlxSTV5R0pJQkJ1?= =?utf-8?B?NmJYNGxTVWMvZFhXQ2xxL1hNWVZJQ1dEeHpvQTZsK2FUMDNnLzgzN2ZGbkIx?= =?utf-8?B?T3RxWStHYmcvdnlscndyamxhY0M1aHdoaDZwTXBpMDRFUDNtMmR5L2RDWG1a?= =?utf-8?B?a0x6c2tFamZkb0oyUkJRS0lpSTl1dzlYSmhsV0JvRDJyZDduaEcrL0ZkS2ta?= =?utf-8?B?Q1pDdG5WMFFRdXY3VEZkNlY1UWJuRHBQWGk0bVJVV2hiU0owTFJDN0o3VU5I?= =?utf-8?B?b01rNEc1Y3JyZERheGRVTXg2WkF6Z09wVk83OWRjS01HYlBSWmVZM2RQM2Uy?= =?utf-8?B?TDdqWjU2U2E3TGRycU8xbzNXY1AxT0w4c0tCbkMya3k4SkljanQxbkNFK3lL?= =?utf-8?B?TEtuN0IwdUd5ZTlvZCt4aEhGU05tYUJuM2I4cTRRUWpmUTBSZTZESmlzWVNL?= =?utf-8?B?Qm1ocllMMS9ZMi90QU9oTlhUZGsxQlV0M3VIMW1VaFE5ZHFDcDNQNUdtbERE?= =?utf-8?B?WjN3L0RMSDdib1Z2Tk92QlRtRXQ4UUt1NjdzbEhiNlduRHBRa0dYM1p5M09G?= =?utf-8?B?YjlBMGdLWW9xb01KMXloL1RxcVRRcGRnTnQ0bTk4dzZwWTIvaEcySEQxTVBa?= =?utf-8?Q?f7krKgkMUO6iXYFeRGoT9rNsEJ69AijxF9KOdY6yYmlzr?= X-MS-Exchange-AntiSpam-MessageData-1: tC0ARSF1jJSRFQ== X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 399663cc-b8aa-4c0f-7c70-08de954adc10 X-MS-Exchange-CrossTenant-AuthSource: DS2PR12MB9750.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2026 08:43:08.7582 (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: KjR21b8s/0/+/kWHSj4IhuigronLbOtE4l4KXEHpGwTRKKkXCEYzkZ3vRMwAUx1XWDLNeqXWdmbKUESyVkbewg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR12MB6892 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260408_014316_430222_3E1BAA12 X-CRM114-Status: GOOD ( 10.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Robin, Jason, On 02/04/2026 23:51, Jason Gunthorpe wrote: > On Thu, Apr 02, 2026 at 07:11:13PM +0100, Robin Murphy wrote: >>>> @@ -2714,6 +2714,10 @@ static size_t __iommu_unmap(struct iommu_domain *domain, >>>> pr_debug("unmapped: iova 0x%lx size 0x%zx\n", >>>> iova, unmapped_page); >>>> + /* If the driver itself isn't using the gather, mark it used */ >>>> + if (iotlb_gather->end <= iotlb_gather->start) >>>> + iommu_iotlb_gather_add_range(&iotlb_gather, iova, unmapped_page); >>> >>> The gathers can be joined across unmaps and now we are inviting subtly >>> ill-formed gathers as only the first unmap will get included. > >>> We do have error cases where the gather is legitimately empty, and >>> this would squash that, it probably needs to check unmapped_page for 0 >>> too, at least. >> >> Maybe try looking at the rest of the code around these lines... > > Okay, well lets do this one, do you want to send it since it is your > idea? Any update on this? Boot is still broken on a couple of our boards. Thanks Jon -- nvpublic