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 EC5F6C282DE for ; Fri, 7 Mar 2025 15:25:40 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0C91910EBD9; Fri, 7 Mar 2025 15:25:39 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=Nvidia.com header.i=@Nvidia.com header.b="E7VWu2Am"; dkim-atps=neutral Received: from NAM11-BN8-obe.outbound.protection.outlook.com (mail-bn8nam11on2087.outbound.protection.outlook.com [40.107.236.87]) by gabe.freedesktop.org (Postfix) with ESMTPS id 30DA010EBD8; Fri, 7 Mar 2025 15:25:33 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=aMNcfv39Eoym8ajki12DzFj4PieFajEnhoPkWEFKvhJPCx270Q89ZmLkYPCqxbg/FCjcj6MuiyAyXwzQwXMkhISVmNhLuR1Izfahifto7+HCT4y6QSoAlAyoqnNaMsTvgReaMdG04CJ9zhFoFMtVtFC2MCquPh2NocAKFN/SYrc0nWCIs+QmhUa8zVUeyOfLtI1EuMcNOLgISeRNST1+3tzB0LnVbpbxflqF7Kd0SONGoRQSrDQ+Fu3ujSg1zbi26DUFQCoxSesDOBobq7lMafibZptm9GKggUCO86ScnUaRs+ui7VlqJoKTBJjHnqZKkfdoAbWhMBKv/g35fFBpAg== 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=kpqw6k60RSDbgfpB13Snac9ebGF0UFBY5DJ4+cl9J4k=; b=HzzU83JQbKdy8i74Ol0qYxDfnJwrY7dFcCBiJOWdLm+B/EqZOqv4/zYhApNSMjmSVg+qGOf3Jiskahv2it12q4ghWEPDKqrwa+F6b7wVNEuS1BVWRSDY0tXGP9qVeOsWaPwf2xhgKy9dvZ//M7ave4a/5AaKC27cEdzLCDKrjB8IUYKYB7K20LGfaZbLFAWVv5gJfiiW5FSsnlUV+VMpMz5hW4aJas4+yROnlMUQDusrbLxG84gkZdst+T2Gt35RyZQDJLvUg9OKten8QjThkchhkHelH4GGalJIxF9+dMLnmbpi4nYJESUFogGSHM3/692tqWEhVHRe84t9BKUEHA== 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=kpqw6k60RSDbgfpB13Snac9ebGF0UFBY5DJ4+cl9J4k=; b=E7VWu2AmeQZCKVIAJHjH+6qYfT0I3ZE6Uw+x5G7k7e93AdIM+SR0nLtajX9Fbn29pMuJltFH4VbaKejfEEzPMH9znl+O5u1AJZZ+JxOOHufg3jLG7XUZr0mxxUMYPjRAtceuazoF6kTncSiyq5XhiY63eJi05RGA/faXidN4B5ZeEr329LKFK7ArEUxiPYDbn0lHHeYzsJqZ54HWiRCrJN6gWQil7jPH4EpAFajk2BnVc7nVajoKnGntm6qPY7dgCmZVBWM0QmkVqMFDW6NnI5qpgqdp8x0cMn2WXIsm2n6hxCL9Jid3MeTA7u1y4XtaYy/+SzyeTwQOAfXzwOWKsA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from MW6PR12MB8663.namprd12.prod.outlook.com (2603:10b6:303:240::9) by CH1PPF0316D269B.namprd12.prod.outlook.com (2603:10b6:61f:fc00::604) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8489.25; Fri, 7 Mar 2025 15:25:30 +0000 Received: from MW6PR12MB8663.namprd12.prod.outlook.com ([fe80::594:5be3:34d:77f]) by MW6PR12MB8663.namprd12.prod.outlook.com ([fe80::594:5be3:34d:77f%2]) with mapi id 15.20.8511.017; Fri, 7 Mar 2025 15:25:30 +0000 Date: Fri, 7 Mar 2025 11:25:29 -0400 From: Jason Gunthorpe To: Greg KH Cc: John Hubbard , Danilo Krummrich , Joel Fernandes , Alexandre Courbot , Dave Airlie , Gary Guo , Joel Fernandes , Boqun Feng , Ben Skeggs , linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, paulmck@kernel.org Subject: Re: [RFC PATCH 0/3] gpu: nova-core: add basic timer subdevice implementation Message-ID: <20250307152529.GR354511@nvidia.com> References: <20250304164201.GN133783@nvidia.com> <20250305151012.GW133783@nvidia.com> <20250306153236.GE354511@nvidia.com> <20250307123255.GK354511@nvidia.com> <2025030753-celtic-quarry-1799@gregkh> <20250307144629.GN354511@nvidia.com> <2025030749-pulp-juniper-c35e@gregkh> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2025030749-pulp-juniper-c35e@gregkh> X-ClientProxiedBy: BN9P222CA0030.NAMP222.PROD.OUTLOOK.COM (2603:10b6:408:10c::35) To MW6PR12MB8663.namprd12.prod.outlook.com (2603:10b6:303:240::9) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MW6PR12MB8663:EE_|CH1PPF0316D269B:EE_ X-MS-Office365-Filtering-Correlation-Id: ea13f8ad-b844-46fc-4d20-08dd5d8c4bc8 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|366016; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?4lD9MA3m7uwHQtQKz3p6zepr0DjUwoJ9sKHLWGqIaPz/JbNE2VNMIPaQBCu/?= =?us-ascii?Q?qfn2fOSRdWv86/EJPkfpZxwdy/vHiSy4IPgncZVksu97SJ68qR3hcP02wG+o?= =?us-ascii?Q?6lYJ2/6dNxuSoOm/EgAlWwudNJuGBzAGy1pceFgeSn8a9I0tCO3/UiVXSLOh?= =?us-ascii?Q?YudxO1zYv67dtXuW99HMvS2zlNUvvj2BN0nm1D5DpPR38P6AFeIIDfzfMmiU?= =?us-ascii?Q?11PzNUruoYDxK1gpF3N4VhlCxy01QiuiRFPAQ8x4TF7UjPFMZTz9FKCevq2/?= =?us-ascii?Q?sTXjwCv5SpBelQaJGbT4U/ATn0oFZo4I5fWPE3KIerDntcaGe3yjqRny1Don?= =?us-ascii?Q?qmOOmHhU3RtYgkAIPRfiRmAD2IPFL3OWgUp1sH/yNShGdPKNtYlNFJdHm4Vk?= =?us-ascii?Q?zacKBQWVX3HfaIo700Yhv94z52YBFWTMXFRkXk/X8F5+5gAo2qwNjVOa3XgY?= =?us-ascii?Q?DeXOYoSWNJG01KhnJN4Qi7UU/zYoJuCDAs0kta2iXbh/JMnBUrmejX1LNxwV?= =?us-ascii?Q?ql0kIe+sUOBTZrlfMf2eTbFd3GoMuZPfEL76mVkLUJBAzRtm0wCslxJQG6HW?= =?us-ascii?Q?IiLCKstE/LwHfMOjhr/jIA3jhYFS5K3LGs894KJVwLv2p0c99VUubEKPzkg9?= =?us-ascii?Q?O7G0vstiwh1zzrAUVv96vEqWv32UZoKQyqj7KWoZdL4XurUkv8TIFsj+7UUC?= =?us-ascii?Q?1fmFe8oL2p5GGIRdWZ1rUza4q2YaX9q6neQXs1rcmBqLnKiZngoR2Mc76gT6?= =?us-ascii?Q?BZQK71hB+p6IcZuk8LPCBOARDRtKod2k/s0/oFJQ9pNf5CoMrBrJErbo7MJD?= =?us-ascii?Q?SyIU9PpBpq4ZzSZvCTCGVR3ZnxurMfDAiP2Z5QRy+gNyerEe5iVzNzvPhBe6?= =?us-ascii?Q?BdgH7ie1V5uHWt1eHy4RJYfc4LUK7zt0C5zWtvBgs9gFwC9ds4Kz83M2Xr+2?= =?us-ascii?Q?l12JG2dXWi3qHn95YitQmnBZ37nEsQDeyd6CKDT8e5+iwcp7m15Iyz6TPROL?= =?us-ascii?Q?EsR0mJup4ErqBOfNCpWBX5SU9jGvgvAULDbFnWgnyhKq6KWzbgi6GIeBFN5N?= =?us-ascii?Q?xvL6dGB4d6FMIhPz+aDDjDpEJYX5+7EMXjD+NtKrZUcSSp8AV6YUuCm/mp1V?= =?us-ascii?Q?+G1jXKcfh5JIE/Fsk1+FYuae75c9El7lLIdHJp3CahCREX8nFCXMGfUgKPQ9?= =?us-ascii?Q?f/ygSV80aIA6Qc4gJ6mCUoNqQ/2lJ2BDS5l1qE3HzYUlZpCyjuWhtIOLXnYf?= =?us-ascii?Q?+cVDAnAOgotrihGV0oews0ynNLU+pRGjYUe1CLZFVqKkziJyT8oxec4AMJ5I?= =?us-ascii?Q?xamlLzYcS0FjNzEBrESCOB67hKmTdkdca28VTWdCdKRRZRyt7XVbLZzyaE6a?= =?us-ascii?Q?FGuJ7IEaKzkDFceeE+fK93yxDsux?= X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MW6PR12MB8663.namprd12.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(1800799024)(7416014)(376014)(366016); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Urql6DXOcSZ2ugTjHnOoB9ZgcqSjKDrwOiXdSKX00UC7OxhtmIG85HMU5Kit?= =?us-ascii?Q?bX3RUfIzRR6MjArbCjChFIBOWYExU0YeTdCNOoNydEvFhBZt26YUFSKiPTis?= =?us-ascii?Q?+G+UVhKRVIlVbkOZc3ZHZ6faXOqgDXmo0VVvljbkSucr8pE6v/PBHuwhnhMg?= =?us-ascii?Q?PngYNH3HpfLtCcUrEllsLYlZdvAUCRCTOCsM8ao9UJD2cAwsazTMpLcHh+hh?= =?us-ascii?Q?5oZjynRWTp67n2kQahFB5UthPMCk0iVIbA6ezbbl72EVKc/TrlJW67QnZu96?= =?us-ascii?Q?Dn6XOogaOF2BWwsv5jcmcGcR4sxxqxM/qsUTH2W1CDbaQCtHIqxqMAexsl1g?= =?us-ascii?Q?2E5GIxJmmOhpf6RwBzHEO86dEL2bVfnoVToDy0xA6AMbJm6lKvv8Xuz3MrNs?= =?us-ascii?Q?I4b9wBsYoBrM1CrX6T6CeLP4huxy8etYE58/82QHSNQ1ql5BF7fHl8G1M1wn?= =?us-ascii?Q?h45f0XITzBi3Pr8llcE0QwaZ3hF5eF7qxf91OCHp1M/bhMPgWs4V9AekVfx8?= =?us-ascii?Q?nGlVawNSyIAS4+D7EHzpCummLqyV8elxWi8CZXsXxGK/MJtTvGqBCe1Y//rQ?= =?us-ascii?Q?C1eQdwW+oXek1iKmPVs1lCFM84s6Us6YiCERdwgfp2+lJSMusQriVIlgfvrc?= =?us-ascii?Q?fB4vaPfQ4zDPAU3ZK+Vk7CIz4llQvGrqYGl33IKwmlqO5e8QADhYSdGaxM4i?= =?us-ascii?Q?u8QDsHaZaKnRJWBEY/fxAct7yUk6So85FDI/20x9X02ux0myxTAYk13yeHl5?= =?us-ascii?Q?hnM/4d+ALkZNT8vCg9XrhnRAUvQbkQC9wSnG5YjbIXGWx0F+glrZ/i39Y3ut?= =?us-ascii?Q?SEVU3mK5TqfICNU2IwGc0sb1evMqbCGvEvxyZcGlCScwvoI8y+0GZfHIKxCU?= =?us-ascii?Q?6wPbrfXlrGJ5orP9bid+//R0xmkO9BTrNFwPV6PGlGcSeEItvRu9zIgdNsar?= =?us-ascii?Q?kEYCjcIYnAxqS4wwiRVv8XfQyxeWssjsA8f6KffdYLPVOI2deSYMdj3jL8Km?= =?us-ascii?Q?AYr2mE6rDbRU52xDztx3ndxTAf9I010VR2pkY0ja+gm631NA9lHF/BMBveqj?= =?us-ascii?Q?AuhsekA7VSQ9hjZ8qBxZl+PAPDwu1eby7twW/G0REJQlUri7DKQIqHQUuR/d?= =?us-ascii?Q?nRACaud144AYmnlgD4urzjv0m+b12Tvk3xTy/H/fad9nGHWDOHYiTInW4ktL?= =?us-ascii?Q?vYJJHJjYMLSlOMZLWliggWznPsXpB2ZSSd0IVuwHlNCFPFM/L1TN8DshP/vZ?= =?us-ascii?Q?k6/YPGx6oHnYQG5bCMFwu2KS+BnhCul453fzFdFNqdfvPIuLKBnEjSPvqvdv?= =?us-ascii?Q?V411a3Vgv03Ukk4wEfaFURCSgiqqfV9R+LMRUkkPF6UZ0+5p2W4FszQtw+9S?= =?us-ascii?Q?Tr2CYBPV36lvA7BtSFeo2dbWKsGUpakyZtZBhpMxCG+kfx4fxlBD4gwLCkxM?= =?us-ascii?Q?iAeRQXTTqThrPGYgV+lyA9CSzBsSSwUIwzSw7y0OwDMYFMrCEmkQ0SxaLrNf?= =?us-ascii?Q?ML4dNdBdwi5Wu7DwGlfcEGc4oLc4ec07xlrwh9pbu1tBc4TBRFz19BZHA4EI?= =?us-ascii?Q?75v0QL94zWk0FY1qsZsBQD8OfV6Tvb93vcwqTA2K?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ea13f8ad-b844-46fc-4d20-08dd5d8c4bc8 X-MS-Exchange-CrossTenant-AuthSource: MW6PR12MB8663.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Mar 2025 15:25:30.6188 (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: rKv8JTolGsMw89U5FCkD2Zz5d2q0XckGKMTa6Vs0Q17SJD5ryDPC+Jgrv5BEp4N/ X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPF0316D269B X-BeenThere: nouveau@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Nouveau development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: nouveau-bounces@lists.freedesktop.org Sender: "Nouveau" On Fri, Mar 07, 2025 at 04:19:30PM +0100, Greg KH wrote: > Just like other busses, if PCI can't handle this at the core hotplug > layer (i.e. by giving up new resources to new devices) then the bus core > for it should handle this type of locking scheme as really, that feels > wrong. A new device is a new device, should have nothing to do with any > old previous one ever plugged in. I think it would break the iommu assumptions to have two struct devices with the same PCI BDF co-exist in the system at once. There is only one HW IOMMU table routing BDFs.. Most likely the new device would have it's iommu setup blown up as the old device completes its shutdown and tries to tear down its iommu setup that is now actually owned by the new device... Jason