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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?N8th1Ng8ZkxcamseaLQZW+EEQfg3bMKZ116Rh+QFTOjioxue8ft921kfp12O?= =?us-ascii?Q?KpuGK6XiF7zx48NaX9yGaytuhssrnx9odJmZFuayYTax4hfm9KcMdolTk3xz?= =?us-ascii?Q?9sGhAg1ck5GdQ4jOnKYa3rOXGDFr0LinDBiDSu+8LtWr5x+wCdcSVzbDS+0B?= =?us-ascii?Q?v+srTgipCi75HYst5FKoRlGfN2wGgmCZ+0xGtmrCfFnswwGneQgYxXpGgBay?= =?us-ascii?Q?4SxcYnaDQRxAX9o5MWunV6l++i6ygDegkVDwVsZHQWHEM/ILhSSKPGy9GbGb?= =?us-ascii?Q?SNCZYRoMSehlLLPKsf2Q5wSJXGpQdu06PPR64Vrej1Tvs0D8S7JS3r5cQ/vw?= =?us-ascii?Q?29HuqY+SUuQLDm1mWXKgI7a3xwKxbpTT2nEhCk7iWJuUVzBW3HHN0qOnoBcN?= =?us-ascii?Q?mrO/W5HTzMcrhE38MnIEDErW3z51S8Za9LxPkMyjnDcQBvTE2MnQ9NI6HJGW?= =?us-ascii?Q?1SmA1xrxiRtfxvkdjFr/7Lex7mmI7r81mPU0T9yqm7M1IAVZ0LZF5x1vb38e?= =?us-ascii?Q?tsyoO356Mgt4WWQk4JnPL9MCEpvZaCaxtLkKTUJCa+ToiIO4c42GUJs7j5Uj?= =?us-ascii?Q?J/SXcMZoneggER/IRbW0iz9nItnHOwQuq5JzGM2RQU3BJdZDkXPDkm371eZO?= =?us-ascii?Q?KFimIm262nXjDf5MZqjLt4MhcHmqPE4dw+kG1gX5iheiWMFZwEnxhB72+9qM?= =?us-ascii?Q?RICo6SY0WC0mReTmFsVSjndiy/Wfp6Uz7NIAyrcfYSNPZJsgY4n0N27q19wC?= =?us-ascii?Q?o5AGPfiHhr3yr2FFrgR1wpH5dv35nRW74rg4mryLJDNE89yBvePYDBPHx4e6?= =?us-ascii?Q?2Cjgrs/iK7KdSv3kTyCdIAcOcc9VmIGVSgNTIM85olm1LucIlOP4UZcNW3IH?= =?us-ascii?Q?EwEmFuhNtphBmjxoUfAK6ExyTCUOSvuWFZx3btPhIwaIp/CXJn31Z5XHztB2?= =?us-ascii?Q?hvWPLrp2iJkWcwtLLfUh+qD2bkqtk9lV6EHQdtuWWu+Is02x5qlAqi8MJ9VB?= =?us-ascii?Q?PqwZ78eUuF41wKH1vCwQNu4zzlTWyzgbKMkR2OlGuD7Knzye5dTWavI0vsVJ?= =?us-ascii?Q?eKb1uP7z5rSTOwBrzwdfGy1HSgbKrQthn3xZskEgf1I8smh7dI5NnH1vDf8s?= =?us-ascii?Q?ZPqEya2UgPCMzu5CTeIpeFoM+J+9OZb5KU430fCQU3EtJoNzDbVgtQd3MApj?= =?us-ascii?Q?HfrLi0yagKQNo8/nKm9EWeVzehDW0JLcDXVLxvgGhm42t/5X5bP4D5GtrHyb?= =?us-ascii?Q?pvaWq/2w2/6GZlDoJT15p8mw3ynGcYOMMWj1WNouxfK31SWw8WQg0cpiTZVJ?= =?us-ascii?Q?5qMitrpkpeNoyGHavkDyHVVhpuMcOZJE1SbQyEdKkDqZ8Tv/b8Kk1EBHAjtH?= =?us-ascii?Q?LSIQKMAk+uxG4W3y/JtdDXf/5FXZjh/1kSxQigQ9DWNxyajTaNlNtRoB7Lyu?= =?us-ascii?Q?Y8XCx2dD1ozthJUTOe+K0yXi6AzZwyPxC6iGFl1kgv9sAD4S+xtRvFO7/Tah?= =?us-ascii?Q?0aD1H+tSDwjDU8rXS685HlmPkxU+OCBWyK2VEI0yX6c3pKcQRkEYbMVxVDe+?= =?us-ascii?Q?bN13B5XJ3Ha85Pk8nMEdPQI5ZmskkGqTVw4avIFb1vOKIqgRYvhjXrN6nDK3?= =?us-ascii?Q?pw=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: 596762f1-f2d3-4b85-4261-08dab5fc654a X-MS-Exchange-CrossTenant-AuthSource: MWHPR1101MB2126.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Oct 2022 20:14:46.3347 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: xi3EeqgOYWxShJNjpQhJ+dL/snkvX6X1CbnV1cLteq3JL5uQfjMYFNKGaYKJ9gUHKdAYO2zAb1VOYR/DHbN2Iu3U8b+QYnyxt4N0MbWlGWw= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA2PR11MB4889 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Linus Torvalds wrote: > On Mon, Oct 24, 2022 at 12:39 PM Tim Chen wrote: > > > > I do think that the original locked page on migration problem was fixed > > by commit 9a1ea439b16b. Unfortunately the customer did not respond to > > us when we asked them to test their workload when that patch went > > into the mainline. > > Oh well. > > > I don't have objection to Matthew's fix to remove the bookmark code, > > now that it is causing problems with this scenario that I didn't > > anticipate in my original code. > > I'd really like to avoid *another* "we can't actually verify that this > helps" change in this area, so I'm hoping that the reporter that Dan > was talking to could test that patch. Oh, sorry, I had typed up that reply and contacted Tim offline, but forgot to send, now sent. > Otherwise we're kind of going back-and-forth based on "this might fix > things", which just feels really fragile and reminds me of the bad old > days when we had the "one step forward, two steps back" dance with > some of the suspend/resume issues. > > I realize that this code needs some extreme loads (and likely pretty > special hardware too) to actually become problematic, so testing is > _always_ going to be a bit of a problem, but still...