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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8WVuukeEm6Vr3LX4BbHDFKGkdy6N884S9hbC8q2ZgawxNNa+6ZmbgAvDSi4i?= =?us-ascii?Q?lj9CpwaLmNpgbCgXAibQMzQXwO8s9fflc37l2/qnDXyaaqjj3SlMNfV1sSiF?= =?us-ascii?Q?/HwZ/MeR9VcS0Uc9M/isG0BcYq3OfEA9Ga3M6qgp4SRBCV4uez1BHaoa6EEM?= =?us-ascii?Q?Y7q7hk8l0b9atIh8rZ6ZpWUIHNiudYAu+w5LC74ERGaMm+B9uR5KgLWLtP0W?= =?us-ascii?Q?T6eJ6om8uZjXVsL0ZO/kbs8S/lnekwgOOjBMfjCTcT5UVb3pLswNOx4aUmMq?= =?us-ascii?Q?78yWUKRK1aGAsHOVIozL5Rr5JHGdYIOWBd8h09DEOFXvbEdxYUuzVHZKvJas?= =?us-ascii?Q?oVLCU81/broOY4YqVHW461eVZnKDvOE0sao/t4yyRUQ5GHpD+nviJQw/wYmx?= =?us-ascii?Q?9zusVIKGL8lCwZUmwpIiwss0fRg2F98rCoK77cI+tWPiSzHgMvthLjmJJC+x?= =?us-ascii?Q?qudfh55BKZuZHplsMnxPpwEduHCtikU0tgcWX+UB32GBpg2ROhRkwTB7gDxP?= =?us-ascii?Q?ig2oUj37hXrczcdTpQtPG3S73CaOYIzM5KnfGp0fxiUhmpShFS+H/QyUGhsE?= =?us-ascii?Q?eFo+SXYYm4DCKniwbSnZMlyKPTJKCSburH7NrIJyEKLeC5PLyHpyuLOew47z?= =?us-ascii?Q?wrWsXCc5nOg9CpEksbc2uoPQW7pZwfy5RBqUl4DYvzI7RI32+otCmTaI0oPt?= =?us-ascii?Q?rPYjMAFSAIt18yXGtJsDZKD9wGlgfYtcD5+wQDBvYUnbgcmVMOVe4sOuBj5F?= =?us-ascii?Q?K9dn7a1M5KOJTWAAyyctcfwbgdqAWfsT+ro6xwA/A6ZAQxZG59SmFJbk28Cn?= =?us-ascii?Q?xP983MTtkHiDPXZ/NhOzFAlScWykp6QvY230LgIi2wt6UE19pWzI6AYz99TM?= =?us-ascii?Q?iGOD+4i6vH1DFkXP06ePxSE9zjsFHT/kFH27DykQvZuMConv2xFfJJtnE6sW?= =?us-ascii?Q?Sx+4LM5mlVMRm+pY5jfxcb6sHMky9njkAV7WQysdHbqnqtspL1eV9eK1cySJ?= =?us-ascii?Q?/f/Rt6LRbN0lR3gxTf8Nj/NKqjefbSggRTrMTn9Vi8/ma3ezdPFDbm8Dk6td?= =?us-ascii?Q?uSLHibIAlIOxMJfvM0WtEl5V59YCAI+tpY5Vz5NH1gsuDiG04jArbGrSabEU?= =?us-ascii?Q?Glt+Lu0OR4C9GBVj6fuXdryDjhGzjVVNPoPbg2Tgy8pRoV88HHBMgV8Dixk5?= =?us-ascii?Q?B1gnZRLiTXvLZC9DLf/+YdmXZzTJbSi+7t3WiRMCs+VvVE7+MAEoDbWj72z4?= =?us-ascii?Q?SPku336HRd/bNKpGNV3ElzFYCn8PNeFOO1+KCxeJGCWNFwkrv8fhDzgNvIkL?= =?us-ascii?Q?/Fj3wpg+vDKEbeoD3jjhaCz7y/8fSsvaoRnxeacOK4Uy4RmHihFGIzmiQgjV?= =?us-ascii?Q?yNoQzEqvB3WfBgK0nCKdGPLQDYnizYDjdVn2WpfeKeY/adzirKtYwDpGURzF?= =?us-ascii?Q?HGWkDSzyPL/6XjRt/9txlSC7fdRUHeCBTvcbxNIH/Kzrn/pZnZhWvC0escNo?= =?us-ascii?Q?q0eS0ZS84Lm9fDbbVymtidWInw0zJQHkgy2YLMGyDCwEZqoMzC/C4NtjTOGB?= =?us-ascii?Q?VC5EhptfJykNmvuQkcw=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7aa3efc5-5a27-4357-9579-08dac0dccec0 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Nov 2022 16:26:22.1348 (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: CFmf2C+O4Of7ui2rzqR1QLMsoR+VH3A6MWEMBOrBL99pkeamSoabEfYLtJRZ8IXg X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB5626 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, Nov 07, 2022 at 11:05:42PM +0800, Qi Zheng wrote: > > > On 2022/11/7 20:42, Jason Gunthorpe wrote: > > On Mon, Nov 07, 2022 at 11:31:09AM +0800, Qi Zheng wrote: > > > > > @@ -31,9 +33,9 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags) > > > return false; > > > if (gfpflags & __GFP_NOWARN) > > > - failslab.attr.no_warn = true; > > > + flags |= FAULT_NOWARN; > > > > You should add a comment here about why this is required, to avoid > > deadlocking printk > > I think this comment should be placed where __GFP_NOWARN is specified > instead of here. What do you think? :) NOWARN is clear what it does, it is this specifically that is very subtle about avoiding deadlock aginst allocations triggered by printk/etc code. Jason