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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6n3jWJPt9GV+Q5tz3vhGgOolYXFrubtGj05YhQ+JQyQyLCbemcpzk4VO/LeW?= =?us-ascii?Q?orL1fzgjhng6A5qWpDOVQa2/dyajKgax9IwsdO90VLiGG0TEyXwmGZGk74vV?= =?us-ascii?Q?+VnnXrupUWXS3q0K/y/fhiYTaGQCdax01Xvychg4NZfY4T1aZg9UNCrC65zg?= =?us-ascii?Q?PzkQmy2lJtQFKo4jufiXv5AK4Kl3eWvMIaFdK+8RUGC4pGP1BE/wJ4Rp0+Dq?= =?us-ascii?Q?lOm+lDoybtdvEUgsYQbPG9yy9+Xq8usOBopQd1qfIoy+1ZfdBadqnqboF0Bp?= =?us-ascii?Q?LYU4/z9DY4/0VoCRc3ah37VV10tv9aKWl6soa58dpjjpDGzTtgxbLa8reClu?= =?us-ascii?Q?cto4xk+v13QVAC6Pc0MgKnVvC1HBzcggmDUy+wrjVFgxXH3VGnh+D7a2usLa?= =?us-ascii?Q?6bn03JA09awSvOJ2lWjExaPvNJWhLce5XbhwZRKFxusfrHVjcbC6d+wke77F?= =?us-ascii?Q?tmZjb6UNDukKOZdyBZ5j5VszEQWgWa+li0YV6cwfjPP4zMMG19Jj2VQFGn8o?= =?us-ascii?Q?StaenxezPyd+x5MjMEczx13+R3stLUMgj3+3aeRh9MvL+MkzhPQxcOy9alMQ?= =?us-ascii?Q?t9M8N2QLeV85K1zQJo4J6SJCoDXGYlcCghq23eekVTi7Gs/2cTHth/2CzY6H?= =?us-ascii?Q?31cvF53kKWoBWUbRo/u1p+LyNgwRJO3IXmDaNx1BOBeJUbANxDj1YU5pTYXp?= =?us-ascii?Q?bMvZTjKfGI4hoh1uWg2b2SJ9nb+UpMIdwHAAmhsigCcqy8UkuIW9EasqlMWo?= =?us-ascii?Q?wzQa/tPHPtljjQo7GfwP6EfqCPU1od36JglLWGbtxWcC3ssBpZEEWk2542Mq?= =?us-ascii?Q?N7ESEI19Hat+v9gwVLGs/GnLcPY+A4iABuAhRxgwoA7DbhWNcEYhqbndPJz6?= =?us-ascii?Q?lRCMQi0qAsx/ICW4ghvZ8XwQO+eb3dOtvTHEzm0koIkAuqdtJSK2C8JL9pCA?= =?us-ascii?Q?NXIq9WLy0vZRkIDCNkf78+tmaxAnzNmzK3y6y6phYAnzp/bc4+rUhVKuM0B8?= =?us-ascii?Q?SVwDI9O8jc+1yLF2wu8PDv0rmJ5K7D72/+jDrne5SV3IiBFo4F+QE+YRJOPk?= =?us-ascii?Q?gxFrIG4KeZqT2f9g5aM1d1iznJKdwEL88J16RZncfRtDYvSkBVN7ynYz5woG?= =?us-ascii?Q?97qOuZu3/rR8pONzl5/ini6d7LGto4bdMr7XeW9zxqI91E+znJL4TPSbulTj?= =?us-ascii?Q?7awz0RBHHraJP+iyBCBe3R+jt9FviS0ip0Maihp5PmL8Xp9WuBz+HwtOU1lF?= =?us-ascii?Q?pxKMmkNXDmCAGfZJALUN+zJL1SFeE07ePhX9toJ8cqKxGn64vgoYUVLQy2Yr?= =?us-ascii?Q?AZkycER+HJW920yU9HSqLBXLv4ElMN1VehEIzvT+Ge2wcT+2yZC4WcjGccJn?= =?us-ascii?Q?/avNmYyGG68OPL01EoyOtGaGd5htRo7AsjTJFqGoaSghyUxJNtJ6WD6+wWpF?= =?us-ascii?Q?hrPWYljzwlw+w4CbIRPLWdDz4uGNCnD7nDNNRLasGquUs/rN7tIz6O0xjwqq?= =?us-ascii?Q?FDSFcQl1oYz6f25ThVP89zPuDwj/yj83pl/db4MaKl2YO9/Hv5wIk+6B1Pkk?= =?us-ascii?Q?XFgFd+aQZK1CRnNq94/v9wE9l4Up7tOSI2xLACD5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a99c4736-fb7e-48da-d52a-08db2106f8fe X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Mar 2023 01:30:03.5746 (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: 8KqAIMhsfee6skSaVUtHib6ZayJsj26gfAgAot8xOH+vh+H8gerEjWgpqLEaAtI/ X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR12MB5138 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 06, 2023 at 10:58:03AM +0800, Lu Baolu wrote: > device_lock() was used in iommu_group_store_type() to prevent the > devices in an iommu group from being attached by any device driver. > On the other hand, in order to avoid lock race between group->mutex > and device_lock(), it limited the usage scenario to the singleton > groups. > > We already have the DMA ownership scheme to avoid driver attachment > and group->mutex ensures that device ops are always valid, there's > no need for device_lock() anymore. Remove device_lock() and the > singleton group limitation. > > Signed-off-by: Lu Baolu > --- > drivers/iommu/iommu.c | 78 +++++++++---------------------------------- > 1 file changed, 16 insertions(+), 62 deletions(-) Reviewed-by: Jason Gunthorpe Thanks, Jason