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X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?V7G807XVR6kr2PJnVA7Gn2HHZe/TGQzJg1mjkk0Nsr/+YIr6wC2RcsOgXToA?= =?us-ascii?Q?1rSWZQIGaWKVvnYiGJ79AoU+/cnAP79/iannXmX7jns4sU6/0IXdx84juf7w?= =?us-ascii?Q?+qDlPTevFiJiMhTkNOYCjWMpQXfU7C06uAW0sTvdfuY26+61K1F+BqDpEK6A?= =?us-ascii?Q?a/7GPHDK4iV6TcN0hDj4b9l9kEIsTxwLjYQfWtWGpxaeUOIa3h18uDZ4Qn/6?= =?us-ascii?Q?0EYWLm5rWhR9lD4esnsAPOJuGjBgMqKJtYpVvNRFmtLyJiBmld0NcZZl3FKW?= =?us-ascii?Q?06lOB5HT9lHLvtUXPuqDHuRX8K1tY/hMCIm1oFo1no9HYs4qM7itElK4HG9c?= =?us-ascii?Q?OfNQflge2zOHR4Su/euYIj9PhMj4Xv/14EyJ761uoR8hFXqGXupobc5Rxnel?= =?us-ascii?Q?DKj6fkUcQGtmD5A7gLrEfexGf/4g2L0FSaQUiLPBqhAc8IrlrF6ZYgBrSFE2?= =?us-ascii?Q?XZ0JfsyaCLoLnOcCRaeZLavR3EfKlPSEFmSQ0Elv7iSbD233j+hczH1vXbAm?= =?us-ascii?Q?0CBVxZdpbM38ey2cRpf6YhI4mdFZ5K9EpPqlwi2zFItFdpkXGI3irG29GaOH?= =?us-ascii?Q?ds/GPpAqA6AhrUHWRA8r3mgV3BjGvTik2tdePKKiZ8Reps0xIVjlwBoVbfIg?= =?us-ascii?Q?lCJ7GnIC6kUORJEWwS8cqxvMzveUylYA6DCYvrofa0SOcTcihHi9KVqUwDTC?= =?us-ascii?Q?RfVxh5TiF5uJb6iRrWO3EK2id1Lil/sOwbuI1TI/pBziFfelMQrOBie+/xe3?= =?us-ascii?Q?89g4o7ptl+yqjr1FVx2wVpHVaSAQcOLAErtBUUiwcbNN22sHnavEm63J9TKo?= =?us-ascii?Q?3mzk85zhXqxNpRNOabeAVZ/z6iUUE/sYPI0flIf6iFgceiXyjbKTfxEfJdUV?= =?us-ascii?Q?A4zRnILz6KjfJMdb9bBi7H0QG1Ul7IbCBndyxnOKMQF4mIoNQpeocBM/pgvT?= =?us-ascii?Q?uQRlaXyA6/kY+Iyl19U4Ov7d/kmZmY/qq3ITJGS86Ovg4LA69Ww9yv6DH2Vv?= =?us-ascii?Q?olFc6la1emNBaMR9va3vDxq6rZH9f098XLqK0YTXdt3fpP5+15SY2RijWsY4?= =?us-ascii?Q?AGnPam4UkB8NJFqZLrRIjI4p3QU7BpkNU1pWffkx5Wwtu2oRQT9/nqy0WRzF?= =?us-ascii?Q?f332+JlSenQpE+kLrVo7ApkCHenyHmrgSOvpTgYEcktr01NZiAdiO6WzZtyO?= =?us-ascii?Q?VJrKZ3AwgHEzBNjG9HMdprfcAMH40RJTbasVxcZMB7RmQT5QSTnbrCcywS/O?= =?us-ascii?Q?ezL1XVqKg5pD1YO1580OYxslU3gdGEfiBbTd70q0UB6dkZjRcbyUPPM473a2?= =?us-ascii?Q?HOMNE9RBmRw1nHA8SzmuZrmY?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0b481d9d-fd1a-4035-85e1-08d8e5b361cf X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB3834.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Mar 2021 00:03:07.6851 (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: VMTHSjyjvQ9DFSGFC/dmqonwJK69D8U9pE3KLbQQfmMaYZc8uOntBiYr+9qUAva6 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4235 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Mar 12, 2021 at 01:58:44PM -0700, Alex Williamson wrote: > Yeah, we can indeed use memalloc_nofs_save/restore(). It seems we're > trying to allocate something for pfnmap tracking and that enables lots > of lockdep specific tests. Is it valid to wrap io_remap_pfn_range() > around clearing this flag or am I just masking a bug? Thanks, Yes, I think it is fine. Those functions are ment to be used in a no-fs kind of region exactly like this. no-fs is telling the allocator not to do reclaim which is forbidden under the locks here (as reclaim will also attempt to get these locks) I would defer to Michal Hocko though, maybe cc him on the final patch series version. Jason