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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?4LrqHoyQCBk0GndY58rVskbGEfwGtTbRNA4cveUjgslJEx7GDadJ3VaciCYz?= =?us-ascii?Q?eHZmfCEzsT7nU7hK419OKqJRbfkugOp4mFiaMu9Phf1EQlg4bF1JMldRSE18?= =?us-ascii?Q?+6n+cgdMTo3ifCvudygrRnG6Wy/bu1WcqC3Dbvw2C80LBCP9KOkaKnWATSSy?= =?us-ascii?Q?9onQr0JeZsqhRxcndzPmZEKestk/heVqn/v7DDUEAWovmI4N2dWOwMVRvv+F?= =?us-ascii?Q?rJ5aFpQKbnCbh9fwDLHjCWgy9i8PjCOikvL8jj9DZkT5lHJsC7gz8Pxu21vI?= =?us-ascii?Q?5aFkI8qV6/NHIUEYqtYQUVc3wEMyZwNf+yNihdKOenMMzq3VBm2GoHF39XJM?= =?us-ascii?Q?5IY/Jk713zaAidtfwgun37CaSEGR61DpF5Tb+FxLtYp1xDxHqifYFovP6x9u?= =?us-ascii?Q?gOVY1PK5xUNzL8XQBUeGaDTTLLh9kIxf0xOXWrndINk7mi416ieb0RLdPFwk?= =?us-ascii?Q?vJ+V72LexK4dVwxaq7gQP2SAt9X2cylB2S9WSg0NkzGS5QlHFRZjf3bV8LHR?= =?us-ascii?Q?FxHEVsIMg3LumsWINpY3qTb6Bh0FCwC8489ZAnUEqmwCB08kbJBfxMGl13xE?= =?us-ascii?Q?6UDlrTsBAzQ79Gaau7HEaUACXo0GzFYBLMZkjOvcUm/MkyjrIetujoR3NqwT?= =?us-ascii?Q?rwpt5Fr847XF2lf8HjG5mJ6T0ksgZMYwhgfeFkv8RbOrFBCdn0fMt18qL9H+?= =?us-ascii?Q?TV8tkHAq9OFY7Jgn62VV2ts6WFN9LP7ybBlR4QgEn+7mx3uf+wKKi4ce1xg2?= =?us-ascii?Q?tkNmFD0K6BYjZxtAU8qKqJHAkRlraZ3wxEdbNMXy1X73Udkgs2X4o2dKH5Va?= =?us-ascii?Q?9g7cwX+wzyZwp+F41X6/c3pxfI0R6wlBgP6NiM13r+MKQPXTimhsBfZMUQFF?= =?us-ascii?Q?0O9eQHqNh8XOnYlpSy4NXrP5MedVwWUCqYrPZ2ZVOJOS7f8DNbsnkYBxKFyM?= =?us-ascii?Q?LaFuXY2MdlNK4V85/8bfmVvq9+ZMjin0WVIoknmYe9a8kh/d6OLcWrYxjVC1?= =?us-ascii?Q?7EoYjVFRcgn4h/moxFzcZue7vJwn2R6Z6UJGYY+9IcDXpnfeJuUDmcGiuOH5?= =?us-ascii?Q?ntSUPmU9lmNLaB3Qo5+W0Usmqcc46M2aoi5yPzmZi8IzLquofYROWdkGQc8P?= =?us-ascii?Q?vFyAsZ00pKE1kdlobI+VQG0q21Kb9zMJMzybBzdkA5IdRYxqNOHNe1z7vmDM?= =?us-ascii?Q?zQdxW15603OOsHX4P96Spx3Qi2oFbgUkkenmCpwNUxlAVZhh76kcCYvHK+o2?= =?us-ascii?Q?UWOLaNHC2bzUmmojVJKUpQyF+EQdwUnGwkaYKVyd3EqMQd9GEkVvjU7H6Lj7?= =?us-ascii?Q?eOjql7SZaF3dgs96wtmSHm0I7TJ9Ir3V6FiliUc+obEayuTrjONB/tpinzjR?= =?us-ascii?Q?MyebPeblRLp++7MXZeacKtWx9ddOdBXc4X/YJVlTeQNXCkq0Uv215NwzykNT?= =?us-ascii?Q?RbqqMEA/t2gbpB1adi4qEazXqFaUk0X09SUoinfT9G5Jf5OlLiGRrBgTLbgM?= =?us-ascii?Q?iAaomO03CdgbWRWnKWkgN/C0VGFtiSm/nN9lFzINh/m9tbAZTi1pufkQQnjI?= =?us-ascii?Q?GPTh1hwWszKP5VxY+1ZueCMsqopKzA4ZtRw3PkCdzob2GXBgGcPQjpIL3mwQ?= =?us-ascii?Q?gWcLNxLiVJspEUl70ow8v9RCmSqZyRyyPcHk1mgfABKLPuxlKESFRGRqQYYe?= =?us-ascii?Q?n8lg3vhKl4SJNCuReT3CJvCtPAet+oOdySQyQ7D+jDZR9xn1+PVYzSAdO0S1?= =?us-ascii?Q?q0TEU2ahMg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 32f83a35-d452-4e9d-b9f6-08da4235e8ed X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 May 2022 12:14:13.6658 (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: oN/gcnrXpG1bVN0XSZ5UGBIYabJ1ptYcTPc4vpl6Q/CTzFcxdzLMzLKfJynGAwnc X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR12MB1638 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 29, 2022 at 01:14:46PM +0800, Baolu Lu wrote: > From 1e87b5df40c6ce9414cdd03988c3b52bfb17af5f Mon Sep 17 00:00:00 2001 > From: Lu Baolu > Date: Sun, 29 May 2022 10:18:56 +0800 > Subject: [PATCH 1/1] iommu/vt-d: debugfs: Remove device_domain_lock usage > > The domain_translation_struct debugfs node is used to dump static > mappings of PCI devices. It potentially races with setting new > domains to devices and the iommu_map/unmap() interfaces. The existing > code tries to use the global spinlock device_domain_lock to avoid the > races, but this is problematical as this lock is only used to protect > the device tracking lists of the domains. > > Instead of using an immature lock to cover up the problem, it's better > to explicitly restrict the use of this debugfs node. This also makes > device_domain_lock static. What does "explicitly restrict" mean? Jason