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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?wCcFB6kLa+QTlIv50Zq36x+U30h/5XmK/dlBsIV4ssL0uJnMPk7Il7R3E3jP?= =?us-ascii?Q?xTUFQJLDvMZtaUzTQoDUNybQx3ARlOvoxpUIRXseHnBVdemM8cleOWFlFfXG?= =?us-ascii?Q?VPovG9yQjXq7DDWk6EODTr+uoHk4GQItFedluU5Xagzs5TMO+VR86/AgKoZW?= =?us-ascii?Q?+74zQ+usOLbJ8lnHwY6BpGlVpF2YC9Za8meyXKNE49gvE2MoTdK8XJn3Nnyq?= =?us-ascii?Q?DFEgtCMCCJ7asZyeGmY/F+nPjHPBMVodKXAWBF6hHgCEj3DwuVLFp2eMkGTm?= =?us-ascii?Q?5lXet2DZUF3YerYtvbn6gffdwdMrLSD1vVCCatiejnZkfTGT63EoCYUJlDUt?= =?us-ascii?Q?fIYdDxGywD4x9jE5Enftw+HiJ1GxDYCZWZ/CHJmtj1v+uL58pGvKs7lPNcwk?= =?us-ascii?Q?hDYnTZDP0BkPXKJPG5Wab3EIBOJ9ljh8MdQvWw66uhDbSJVtzupXTWz8OY1/?= =?us-ascii?Q?zmwPO5q7/SoFcgpRK8NP/uz3BeJUOhgq8+dOUGccRZkW2zGyA7XjzgDhyo+q?= =?us-ascii?Q?jniyFCwTD5XVUoXAS6+RGTuKufdU4zuVmvfpfl0GMKJwM4KFRzSurh34q6Su?= =?us-ascii?Q?K+/iTS5aNQj0ZfBYZic2b0MGeXSgDeEmJjjXJisJMqquPDZcGQHRf6Q8qWo4?= =?us-ascii?Q?03jUZ22pMe/VWgst9e1P5hUKn/W4vP3VdWe/4lV1thmimAdvRiub1lyi3mIh?= =?us-ascii?Q?VAjfvqrUs2oQTIdN3dJyfxTLyL8XQhx04zNNizqcj6KnuaigrSWou7BbaO3i?= =?us-ascii?Q?eshBbyg6jigNM0GDqbwNJNaFR16kf+MpxSgii24vVy9jV8Ns+vICVTWv8ijb?= =?us-ascii?Q?iN5aXj0aZA3yivXIV13APWrbaxsrTInlVhKdNVgPYUaqeMtL2B/75jWDbgUx?= =?us-ascii?Q?QzvPMZDUvzidD3iALErE+SFb5z5u3Fk6fuovW1ieGWx+2l1BhJogee3rXWlJ?= =?us-ascii?Q?vEkTSaNGdgvZMzFo9WDaNarU2X9yB4Ulu8Hny6LNWm9rc1BGsgzRFB5ZEsxy?= =?us-ascii?Q?J6BdvJ+iJkMoG1b54DXZ6rzztd3jwHXO9OYEt7ijsJwsHWOD28hJMge1vnwG?= =?us-ascii?Q?oZtj8sBQvTXsjBi7xAASlRpojwYXIBkNUWs19kzF9v/Hk8FRvW00/S0zVOGq?= =?us-ascii?Q?yQN1yUO9wM17GVruVXx57OJj/dmXTtBGjXiJcbbEWB82SMaB0Bb70ZIbUv6R?= =?us-ascii?Q?nh5sFMc4ZohC4Trgf1434fs842xzVZLFBKOKlDkySdIwf/oXBz5iWdbZXaAn?= =?us-ascii?Q?RWCp8ue6k1WmoD9QVTIEhbG+3G0C2B67LJqbYtP4iVXwHBqn7431Wt7LdXhG?= =?us-ascii?Q?n85k3+Po3JUqhFR/iKGTAFDMTAp50rDi7b0CP01BzV/CpY5mDv4dnVPO2xkA?= =?us-ascii?Q?WuAaWx84bbUWlewIhe4OrpjEx7RDi3c7KjJXUS2IJQzRWuQKsOOKZw5sQ9sT?= =?us-ascii?Q?uHTd7zWPvfoobabj74G1XchO0EzYQSKz2eJL5QOIzaM4dA9oKkrj9DnMTejU?= =?us-ascii?Q?rwX2l4xxxVPFLM9tGa62ZuHB0fDUe/CNkdq+H3bvfdQfvvOlZZSRbHuwl62o?= =?us-ascii?Q?glIzqQCGShQHRdLjb6rZ/bl0YVVKKuOv7ygZZ5mn?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fec64f7e-82b3-43da-1c56-08db02f548db X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Jan 2023 19:07:51.6556 (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: lGt2ziMLntjvwODDVvo41bELdbiGyNxQPqC/rb5R7xNLAdUr1hdwki/CC6VI+W3G X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB6004 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 30, 2023 at 11:03:09AM -0800, Nicolin Chen wrote: > On Mon, Jan 30, 2023 at 10:59:32AM -0400, Jason Gunthorpe wrote: > > On Sat, Jan 28, 2023 at 01:18:10PM -0800, Nicolin Chen wrote: > > > Since the list_del() of hwpt_item is done in iommufd_device_detach(), move > > > its list_add_tail() to a similar place in iommufd_device_do_attach(). > > > > > > Also move and place the mutex outside the iommufd_device_auto_get_domain() > > > and iommufd_device_do_attach() calls, to serialize attach/detach routines. > > > This adds an additional locking protection so that the following patch can > > > safely remove devices_lock. > > > > That should be two patches then, this is just moving one line of code > > from what I can tell? > > The mutex is used to protect the list. So moving the list means > we'd need to the mutex too. What this patch does is to enlarge > the protection scope a bit to cover iommufd_device_do_attach() > and iommufd_device_auto_get_domain(). That doesn't explain why iommufd_device_auto_get_domain was changed around, it already had the lock Jason