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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?BMfpS0RgvRJJ9XDNz1dx03LIc9kEMfQOkGilWd/Md/6O/slfLYzvroNxGoRz?= =?us-ascii?Q?WDipeYRRThWVQNIYBY+sqSPE5lNrM00lav61+gUR9+LxbqlX2armoNf7SSHY?= =?us-ascii?Q?8H2kcweEf/7VZt775ActFyvXi9w01EljjQtXDLDJ1VOQqyTpEFiBGmvYwPZB?= =?us-ascii?Q?yZ9UEo2LL04OtWHEDb4d6MEs57I82LQvNH6gt3yyGJZgeEj/SuEaW91ZjiM5?= =?us-ascii?Q?wlmAdV71KvczQuQM0byo6onzekkjZ6kVnzKjiNIwjUZk4eU4ahwcDbtpW1rk?= =?us-ascii?Q?OGQrl6CBoZy6hSUFYQ5hamB4JTKelALG2tZ2GpY2jk46NuFGmhL8BPEThoU5?= =?us-ascii?Q?7r8jDv0V6CuxTBr0URlGLZwroxCwByb+K+BpdJbFBR2QzcpIo1m6WXwS/szX?= =?us-ascii?Q?QFmRc0FjM27IxYhLVPTtzV96d3dAARbY4El32Ax7v9FUJTbuF4ZpKD3QeBp9?= =?us-ascii?Q?+m0T66VhwrPe9sUwW5IwdAa74uMAUyR54+uuyWLYqsFO4NRn/wHZFtV0wvBE?= =?us-ascii?Q?IqEUWuYkFtg0LI/IHJ+LXupOZiGRY7kdzs5FHRIEr6hAz7mrPHT6thxXAlUL?= =?us-ascii?Q?8a6njYpUcIecvsFFNKN8Wo5gVTiA8hwHoT+ChXuqnjgEdVgeEHb9Qv5mM/ZO?= =?us-ascii?Q?0ueaBpLET5CTSeID0rot0MmHiQkVFpPfvcrzuozX/qUzgJy8vzRiGKfcj0+F?= =?us-ascii?Q?UwRPQLvzIpAM1kTTYOpAQgmnnX3ZyCnciP/DCSauYiUyuwMSLMiapCnO9RXA?= =?us-ascii?Q?9ksA8gDmfXFCbVlitKqxh4Ak2ovnXJX5AX/u2J3Xg2vWnw4Hf6/++xuJ/a/y?= =?us-ascii?Q?iimmSI2IZipfHgwBPs3UPtbmKoAOUgeWoYDAzfUQicCvMkA6LjS+BH8hToZM?= =?us-ascii?Q?Oes8zPbOtzFGWCxo3txuMDa13JeEW3VFgQ9R1F3A158rD+McEgme491cuF2K?= =?us-ascii?Q?5TY/HzlS9nZBQtsqwct2jyIvdYjYe2iKLy+eMWrlhF+Tdf1j+4jjPb+tVx4W?= =?us-ascii?Q?Ry7P75t55v/gmthFbjdXvScAApJxfqshedmvlx3PpP44ahWVCta5BQlSgv8o?= =?us-ascii?Q?8upaoFOj8J4Je/PRrAXnqqhRGFVAQ8uOwPsgu7f5CoRmGrTQw60iZnUZ+6Y+?= =?us-ascii?Q?9GIxSPBunBmntrHvKG4ducb7OQl3mS4Dgm4Sfsah3rdD3Wf5cEdX9RJw5tnE?= =?us-ascii?Q?l2qlZl17LZ9nYicOIcgR0hu+nR5wO7sg92Zc5v43yj5Du94AU08EExCEQ/5t?= =?us-ascii?Q?IPU2I5lN6Rw/dLmDznI2GdeZA5iFbAJZk1BBM0gbspgrzXTcu4K+HtkF0v3h?= =?us-ascii?Q?0dlgsTE3eNMi6FLFOap3v5Wq1HKEsPFbRtS7Ht4Kp11YTyz2um3kO5XCbBiU?= =?us-ascii?Q?aIRxgnvR8q5JtlgzC9B4iNxyn/KZBcsdA01GXVoDe20PzcEt0FDfPGJm8CZi?= =?us-ascii?Q?SDZAx/KRGkhghYY8K2hyznY/c7oilXvL4QQVQRg4mw73uRzZxBoH8+eKEUFu?= =?us-ascii?Q?//P5uNr4afZWnKMdvqB3OD1QpHtzbsfpeyCWpWroanCnUuEoZhOKdZ/ssHtj?= =?us-ascii?Q?NhF57uBF8C6JAcGC43A=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9d0bc661-47c5-416d-940a-08db8c70a9dd X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Jul 2023 18:06:11.8699 (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: JCzd2GyeFSTC8FxmpLBZCsgCCPlHZ9n9G69mvSprh/MhfUjW2nTqpgnJAywyU8W0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB5642 On Mon, Jul 24, 2023 at 02:11:44AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Friday, July 21, 2023 8:02 PM > > > > On Fri, Jul 21, 2023 at 07:10:57AM +0000, Tian, Kevin wrote: > > > > From: Jason Gunthorpe > > > > Sent: Wednesday, July 19, 2023 3:06 AM > > > > > > > > int iommu_device_use_default_domain(struct device *dev) > > > > { > > > > - struct iommu_group *group = iommu_group_get(dev); > > > > + /* Caller must be a probed driver on dev */ > > > > + struct iommu_group *group = dev->iommu_group; > > > > int ret = 0; > > > > > > this is called in the probing path by .dma_configure(). > > > > > > the driver hasn't been probed yet hence the rationale to not > > > refcount is due to device_lock() instead? > > > > At this point the driver core has partially attached/detached a driver > > so I'm considering it part of the probed driver explanation. > > > > Really during anything protected by the driver core probe path is > > assured that the group cannot change. > > > > Probably this worths a slightly different comment then? How about /* Caller is the driver core during the post-probe path */ 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 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 61B29C001B0 for ; Mon, 24 Jul 2023 18:06:30 +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:MIME-Version:In-Reply-To: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=SfxpQaauhwWTXAZnuNjUayxB3U7Aacp3LW4rwbmjfpE=; 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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org On Mon, Jul 24, 2023 at 02:11:44AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Friday, July 21, 2023 8:02 PM > > > > On Fri, Jul 21, 2023 at 07:10:57AM +0000, Tian, Kevin wrote: > > > > From: Jason Gunthorpe > > > > Sent: Wednesday, July 19, 2023 3:06 AM > > > > > > > > int iommu_device_use_default_domain(struct device *dev) > > > > { > > > > - struct iommu_group *group = iommu_group_get(dev); > > > > + /* Caller must be a probed driver on dev */ > > > > + struct iommu_group *group = dev->iommu_group; > > > > int ret = 0; > > > > > > this is called in the probing path by .dma_configure(). > > > > > > the driver hasn't been probed yet hence the rationale to not > > > refcount is due to device_lock() instead? > > > > At this point the driver core has partially attached/detached a driver > > so I'm considering it part of the probed driver explanation. > > > > Really during anything protected by the driver core probe path is > > assured that the group cannot change. > > > > Probably this worths a slightly different comment then? How about /* Caller is the driver core during the post-probe path */ Jason _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip