From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from CH4PR04CU002.outbound.protection.outlook.com (mail-northcentralusazon11013034.outbound.protection.outlook.com [40.107.201.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 00043322A1C for ; Fri, 16 Oct 2026 02:47:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.201.34 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792118840; cv=fail; b=p2w4pxSiJDT4+Fh0IIcgvrTaov/cFsW1yihhpqdVurSEtaVB57i4EOgRMbEeqE0tXVBCMPegYEIx8PhNzzOFDsojT4i6AcCDl3D9a3CiV+PHVtILOnz0Alh9u0HrTppql7WXGXchw7ALL8NmRn8Bioxh9X7C3VLakQKNnX6bt0s= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792118840; c=relaxed/simple; bh=HSHUFOgCMC/DguV6bQPoeDcRhsazt0sN2yi+ac74SKI=; h=Content-Type:Date:Message-Id:From:Subject:Cc:To:References: In-Reply-To:MIME-Version; b=UWLEaFRFiQiZrgZnpN+uffnJBPEq+IJMJz1MAD8/4n7gqMmU2QKyX3N5GK5OVF89bla2w0KbqTzAxqjJxHu0/9qVXcA7X0Cfd6Jt61kDHCMUV23LGboOG2TyiwiBy2wsbYcQnxUGFdzK8IzWaiBd07tCqBaHTgEXfnigWMKMQzg= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=FTqAzh0e; arc=fail smtp.client-ip=40.107.201.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="FTqAzh0e" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=wrvJ4gwJBxzpqHMBcYTAVgKje9UFfwltAwn18qrULoOevzjXE6Fomu1EXC8NPe9OW36q7fdv81QPaNMdvXmEt21fK6gbeHpeXWHZHvQxG6VPymTnUmBPi/N9t1f5FePmrAugMWs+3g+AxfubMP1EBFTlvJZogBsXqpZOgIz5A3trKP3t9GzGnm2wkwQeQwZclPDBBJot8HJWmcaBgWV1cPhFJC4hAlrepRAxR0RUJmI8bT+B5PH1WIs/kNxGjLdNxZi0Eh3Lu0v+c7VkIilWOYANh8nn0DaFPLHkeW040zKM7RYqlctfZCMcHsXNoZffuwuzxroVE5G7JSb62PXZVw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=4gd+wJ8e/raeP/kYrCpqeiQEpUNcMrUpqW5ZvvKS2Rs=; b=DYxhHgmfor7Nt1BKvoqToSGy3NLajuK3DkdeUZ1tHA5qyWME88quBC/sWwwj+2VXJTjYTQufv44KvtoalhIE04YCfZaCFxCNhg+njwR6JBlJAYHqIH33zwEPCN+HlvnDMhCJAmYsFNNkXI/FTBZdxBK3DW7kXYVzfAt0z/JlZ7X+Bl4Y6ivK7eiuSExpzHCym9V4HRN9JTClkn5MGURdrg/+8wQZ6vtOhKI8lDq3L34PsaTBRS4yjr6fGbWrFdfAyIrZdiX1l8vbHoTBf2M/hK7SUgiQlSf8/1XGdxRiXRBAdZ3nSWExofTZsXNJqEbs0cLDpeKtKQJ2ZAE8O5HjUg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=4gd+wJ8e/raeP/kYrCpqeiQEpUNcMrUpqW5ZvvKS2Rs=; b=FTqAzh0eoHtfHa84KS84sbt9TpcXbmAjmqfiJGfnp8JSxiXMWmIjweIjT82sFchl7JFjJO0QPldWqRMRUX9Lug2Df+RATTHLCCxcFsR4yEYHbWGCc1hBHePYhetO6UD8+a0i7HJnacQAZvgigrmX8PlOHamg8snrNGhH8t9Ib7Eiez0y8LnFIMes3bfB++x7f1bIl0fbaxYYi3Y9hCrRpc1C7g1XiYNRUQHh6ieBP+oPp6+l8eV9y2blLq0iVubxd2kBRQyayUGLZkLrunMPr5lg5ho6kTH/UNlo0EBTxtLvH+boeiB/X6t3uYbdHyXIlBo5sIv4ks0lD396sbMKAQ== Authentication-Results: mx.microsoft.com 1; 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 DM4PR12MB7765.namprd12.prod.outlook.com (2603:10b6:8:113::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.496.23; Fri, 16 Oct 2026 02:47:10 +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 15.21.0472.016; Fri, 16 Oct 2026 02:47:10 +0000 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Thu, 15 Oct 2026 22:47:09 -0400 Message-Id: From: "Zi Yan" Subject: Re: [PATCH for 7.4-rc2+ 7/7] mm/rmap: re-enable discarding lazyfree THPs at PMD level Cc: , , "Zi Yan" To: "David Hildenbrand" , "Baolin Wang" , "Liam R. Howlett" , "Nico Pache" , "Ryan Roberts" , "Dev Jain" , "Barry Song" , "Lance Yang" , "Usama Arif" , "Kiryl Shutsemau" , "Lorenzo Stoakes" , "Rik van Riel" , "Vlastimil Babka" , "Harry Yoo" , "Jann Horn" , "Kyle Zeng" , "Andrew Morton" X-Mailer: aerc 0.22.0 References: <20261015-anon_vma_uaf_fix-v1-0-7b977303b42b@nvidia.com> <20261015-anon_vma_uaf_fix-v1-7-7b977303b42b@nvidia.com> In-Reply-To: <20261015-anon_vma_uaf_fix-v1-7-7b977303b42b@nvidia.com> X-ClientProxiedBy: MN0PR02CA0006.namprd02.prod.outlook.com (2603:10b6:208:530::24) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PR12MB8374:EE_|DM4PR12MB7765:EE_ X-MS-Office365-Filtering-Correlation-Id: 2d5fd1cd-4167-478d-0af9-08df2b2fc698 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|23010399003|376014|7416014|366016|261009223027099003|10067099003|921020|11063799006|4143699003|18002099003|22082099003|56012099006; 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Discard lazyfre= e > THPs at PMD level again. > > Assisted-by: LLM > Signed-off-by: Zi Yan > To: Andrew Morton > To: David Hildenbrand > To: Lorenzo Stoakes > Cc: Rik van Riel > Cc: "Liam R. Howlett" > Cc: Vlastimil Babka > Cc: Harry Yoo > Cc: Jann Horn > Cc: Lance Yang > Cc: Kyle Zeng > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > --- > mm/rmap.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/mm/rmap.c b/mm/rmap.c > index 1131b76bbbc28..805db93fe0428 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -2275,6 +2275,17 @@ static bool try_to_unmap_one(struct folio *folio, = struct vm_area_struct *vma, > } > =20 > if (!pvmw.pte) { > + if (folio_test_lazyfree(folio)) { > + if (unmap_huge_pmd_locked(vma, pvmw.address, pvmw.pmd, folio)) Sashiko mentioned that unmap_huge_pmd_locked() does add_mm_counter() without calling update_hiwater_rss() first so that peak RSS can be under-reported. Answer: yes, I fixed it locally by calling update_hiwater_rss() before unmap_huge_pmd_locked(). > + goto walk_done; > + /* > + * unmap_huge_pmd_locked has either already marked > + * the folio as swap-backed or decided to retain it > + * due to GUP or speculative references. > + */ > + goto walk_abort; > + } > + > if (flags & TTU_SPLIT_HUGE_PMD) { > /* > * We temporarily have to drop the PTL and --=20 Best Regards, Yan, Zi