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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Nov 2024 04:20:18.9872 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 54a95eff-157b-4710-4f53-08dcfee37d3c X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.161];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BN1PEPF00004680.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB6653 On 11/6/24 1:23 AM, Oscar Salvador wrote: > On Mon, Nov 04, 2024 at 07:29:44PM -0800, John Hubbard wrote: ... > Hi John, thanks for doing this. > > Reviewed-by: Oscar Salvador Thanks for the review! > > Nit below: > ... >> @@ -2363,8 +2399,8 @@ static int migrate_longterm_unpinnable_folios( >> * calling folio_isolate_lru() which takes a reference so the >> * folio won't be freed if it's migrating. >> */ >> - unpin_folio(folios[i]); >> - folios[i] = NULL; >> + unpin_folio(pofs_get_folio(pofs, i)); > > We already retrieved the folio before, cannot we just bypass > pofs_get_folio() here? > Yes, you are right. Andrew, can we please add this fixup on top of the commits in today's mm-hotfixes-unstable (or, let me know if you'd prefer a v3 instead): diff --git a/mm/gup.c b/mm/gup.c index 0a22f7def83c..ad0c8922dac3 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2399,7 +2399,7 @@ migrate_longterm_unpinnable_folios(struct list_head *movable_folio_list, * calling folio_isolate_lru() which takes a reference so the * folio won't be freed if it's migrating. */ - unpin_folio(pofs_get_folio(pofs, i)); + unpin_folio(folio); pofs_clear_entry(pofs, i); } thanks, -- John Hubbard