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dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) by PH0PR12MB7011.namprd12.prod.outlook.com (2603:10b6:510:21c::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.546.22; Wed, 28 Oct 2026 02:08:14 +0000 Received: from IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16]) by IA0PR12MB8374.namprd12.prod.outlook.com ([fe80::d85f:4c87:ae84:3f16%6]) with mapi id 15.21.0546.021; Wed, 28 Oct 2026 02:08:13 +0000 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Tue, 27 Oct 2026 22:08:10 -0400 Message-Id: From: "Zi Yan" Subject: Re: [PATCH 12/46] mm/huge_memory: fix livelock on device private folio Cc: , , , , , , "Josef Bacik" To: "David Hildenbrand (Arm)" , "Andrew Morton" , "Johannes Weiner" , "Michal Hocko" , "Qi Zheng" , "Shakeel Butt" , "Lorenzo Stoakes" , "Kairui Song" , "Barry Song" , "Axel Rasmussen" , "Yuanchu Xie" , "Wei Xu" , "Baoquan He" , "Baolin Wang" , "Liam R. 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This is > precisely what we do in do_swap_page() with device-private folios. This > avoids possibly livelocking. > > Update softleaf_entry_wait_on_locked() documentation to clarify that > device-private entries wait until the folio is unlocked. > > There seems to be no compelling reason to backport this to stable > kernels unless we actually see problems there. > > Fix generated by an LLM and sent by Josef Bacik in private. > > Fixes: 4964099163d0 ("mm/memory/fault: add THP fault handling for zone de= vice private pages") > Signed-off-by: Josef Bacik > [ david: simplify patch description, fixup softleaf_entry_wait_on_locked = description] > Signed-off-by: David Hildenbrand (Arm) > --- > mm/filemap.c | 4 ++-- > mm/huge_memory.c | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > It matches what do_swap_page() does. Makes sense. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi