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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?UyxRvfXxOIjJqpagCbeDJlfQyRIOhZUP6BMJF6uSEZZ5RlTlLHHRu7/0eO/p?= =?us-ascii?Q?ypa0rIMipo9m0zIu42lGqc5n6mQeTiFf0h7Sd2SKoPh3yXxjBYwZSgpG6ePm?= =?us-ascii?Q?Qp2JdCGKPJl8kUHTuCFH6ZVjblS26nyuiD+L2Bba1v9Tq8NjbYemN/5QsaHT?= =?us-ascii?Q?dOFxyta+WPlOAC8iYoAqI1r/T6uM16NBAppk6dIZCtwy1uFSQmFJ5dgtSjCC?= =?us-ascii?Q?97KlSI8iO8pHhKx62ATsHSW4tOAPxGx7Frp9f+1iY2xDCKWv/PNIdDrjWh06?= =?us-ascii?Q?L8a8LT7BGZ98XYFfjp8d0COwrER/tsnJ6cXMskP/88bwZvzH1pNeZUY0qf6J?= =?us-ascii?Q?dleid3jueC98gnwL1KwEuG/3GeNnDbXAhmuvLIkyKflHQAwLiYqk+Ksb4H0P?= =?us-ascii?Q?PSZRnDpDtSBvpS2LIshbA+uzojX3C7J3Si2fxOSKJTexefo2C8Fr/Sh7+0YZ?= =?us-ascii?Q?kbwlo+QSmx3KLnmTblWfZZL9ZYJt1tCPUaLZ16GxcfUQlLdpL1OEpiCRky/0?= =?us-ascii?Q?yl6alk72qW6CsJq2NC+ta3aJ/1/FaUPIj+kuRnB+DRG7vprUS4PXap9lhRKA?= =?us-ascii?Q?giPZW47IjIYRFAT8oNkoxV4P/IvUrwD88cSgLZ9RKT4c8YnA2CVAQ4Fp8RA5?= =?us-ascii?Q?wQp4pwn15KI75BcueBkkf5wdXr1w0mBHpTzscjxmFGjuxtcN46IIVAIB9wGV?= =?us-ascii?Q?UCGNWbM6rlagEqWtJ67lDCXI7HwtZfCwF1mUhBRdl3Y/poXm33wXnVZt/7E+?= =?us-ascii?Q?zWOAO1JDwPInLxEKb6rJdKg9Keqk3GgqmqjdZPiRY1IXzs0B6LVQ4o1dM+mU?= =?us-ascii?Q?MS9CoQrdwGKHP0s4EaQpf07tiRK5JxVavBeBtsjairJojVviWS2+Ihi54PX9?= =?us-ascii?Q?sSL49a1lHXkSWxW8vyhwF4ns5ik+pitY1rGBRHuUM/BVgcYzOg2fgSNnOGg/?= =?us-ascii?Q?Re/Ij0b7i4hur1h/0tGu9pwPGcLSynQffPEAGzILNpXI8aXMlWuUpWQgNsp/?= =?us-ascii?Q?g3u9G6ZAAlhc1QZDbyvRQGqPW6kU3kjB9m8Smdn+F/ubKlLI/Yuz7AJZhprU?= =?us-ascii?Q?nMQhf4UEw77rftExzOho/TeMH2B2bndalHrHlH0o2L8g2M28kCAcrP0Zh0lr?= =?us-ascii?Q?zo4ek60/7/87FVHPPVW8Ak9EUNfRHa5I36DuUboh9r0ZvZFmGzWvtfT5CkTe?= =?us-ascii?Q?gy8USiurNxE1w0J2DXaEPbxx93IXKNhCMd4Jr2ybQ9bS0517Bz1stI3JOCMf?= =?us-ascii?Q?6QE62gsjRyoZgJktVPt5Gq6CD64P+1HMlx84ClbWQA6IvsM+Fy2W9Vfd05go?= =?us-ascii?Q?wkUbQMNuDK/g8amZDtBcyTVXdKj7krI5U6Ju6lFc9g6l5o1CxTGg9od+qAU4?= =?us-ascii?Q?t1vc/Pf5BbFlq/kmbpTIF9DrgSNP8GAcC6zWdzTy/ikcwDxtQkgqO8J8GUI1?= =?us-ascii?Q?RiUIQuVMyQAppvKDJAm+ZlbK8hS1PFm5in4jMLBjnUg9t+u5dnB6VXBdn3g6?= =?us-ascii?Q?JDIwTU10tQI1uSPinfFxjsLQ3vVeQlPmiixnslwd40AEroYJRf4QX62fLn96?= =?us-ascii?Q?/OZ0N0REAgAsVAYstF8N0dHx0GQjvS8xCBNUNd8f?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5c843fd8-9363-42e0-c457-08de13da3c52 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Oct 2025 15:21:57.0073 (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: J7v0EzCxlKEgfEDcR6vago/72UKYBjRVZ+O34/szHhWyHK43wh+ooPeq90Ibflsd X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR12MB6476 On 24 Oct 2025, at 11:58, Lorenzo Stoakes wrote: > On Tue, Oct 21, 2025 at 11:35:27PM -0400, Zi Yan wrote: >> folio split clears PG_has_hwpoisoned, but the flag should be preserved= in >> after-split folios containing pages with PG_hwpoisoned flag if the fol= io is >> split to >0 order folios. Scan all pages in a to-be-split folio to >> determine which after-split folios need the flag. >> >> An alternatives is to change PG_has_hwpoisoned to PG_maybe_hwpoisoned = to >> avoid the scan and set it on all after-split folios, but resulting fal= se >> positive has undesirable negative impact. To remove false positive, ca= ller >> of folio_test_has_hwpoisoned() and folio_contain_hwpoisoned_page() nee= ds to >> do the scan. That might be causing a hassle for current and future cal= lers >> and more costly than doing the scan in the split code. More details ar= e >> discussed in [1]. >> >> It is OK that current implementation does not do this, because memory >> failure code always tries to split to order-0 folios and if a folio ca= nnot >> be split to order-0, memory failure code either gives warnings or the = split >> is not performed. >> >> Link: https://lore.kernel.org/all/CAHbLzkoOZm0PXxE9qwtF4gKR=3DcpRXrSrJ= 9V9Pm2DJexs985q4g@mail.gmail.com/ [1] >> Signed-off-by: Zi Yan > > I guess this was split out to [0]? :) > > [0]: https://lore.kernel.org/linux-mm/44310717-347c-4ede-ad31-c6d375a44= 9b9@linux.dev/ Yes. The decision is based on the discussion with David[1] and announced = at[2]. [1] https://lore.kernel.org/all/d3d05898-5530-4990-9d61-8268bd483765@redh= at.com/ [2] https://lore.kernel.org/all/1AE28DE5-1E0A-432B-B21B-61E0E3F54909@nvid= ia.com/ -- Best Regards, Yan, Zi