From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4BAB3FCC073 for ; Fri, 6 Mar 2026 20:46:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 57F206B0005; Fri, 6 Mar 2026 15:46:01 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 560D36B0089; Fri, 6 Mar 2026 15:46:01 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4600A6B008A; Fri, 6 Mar 2026 15:46:01 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 337F66B0005 for ; Fri, 6 Mar 2026 15:46:01 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id D6F7D13B5BC for ; Fri, 6 Mar 2026 20:46:00 +0000 (UTC) X-FDA: 84516820080.20.A05D5D9 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by imf10.hostedemail.com (Postfix) with ESMTP id D1693C0004 for ; Fri, 6 Mar 2026 20:45:58 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=IZDBISFp; spf=pass (imf10.hostedemail.com: domain of anthony.yznaga@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=anthony.yznaga@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1772829958; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:references:dkim-signature; bh=n0ppwyNbw+EN2W8TjeTFyB8h2S47qibDmv1sVABh9ZE=; b=ILJz0VU2NEfXkAV3l7sj0eq5stSfD07LFdmcMY/cynq/GG+S8CLq3yz/qcP1RnF8s2ViYx l/diJgmQOfyoNq+MTnVdrILiHmxR+Y6zpvB3aLQ70hKOCxj+c8kMD8Ad8nB9bBl9oucAEn 3gRYY20Nfgx2nvULVxKSzIxfMwhV38Q= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=IZDBISFp; spf=pass (imf10.hostedemail.com: domain of anthony.yznaga@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=anthony.yznaga@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772829958; a=rsa-sha256; cv=none; b=QqkgKdkGIDerMFJp1+jhUpkFy77iaYGhbcBIvSYqECcEGGzaxxhNgy++pBAl/tDkaL9Apq VwumrhLeiQH/0XQAj8xE8J1To7g70csgf71CJrmN3PyIrMLadCpgUEOE7gcyNbziY5l0m+ KW6ZOwqdxKhPez+77qi5maO64i885KI= Received: from pps.filterd (m0246631.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 626JPVMQ3781939; Fri, 6 Mar 2026 20:45:54 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-transfer-encoding:date:from:message-id:mime-version :subject:to; s=corp-2025-04-25; bh=n0ppwyNbw+EN2W8TjeTFyB8h2S47q ibDmv1sVABh9ZE=; b=IZDBISFpl+2YZmjDE9sE/7TeDpIhDa6CNFMGEaRJLMceP QONHNuJpWOKxqFg5BZnaxcALfhM9ITThVeRml689W17L54rYmeuJEXjx+n+aCo42 lzyIGHaCXJSlA6lWXwo7Phq8eJxOmgmeg4PxS73xGUer7pxCQ5/v3xZ4TBMsiK/a jFl/9lo3fhqYlQq68jRULcKMKes9zxNyVT546AfrD6l3CbLeOlc96feVMLFimvqA 9uesaCpsxkhjKfOBNiI0i9RK4nXpPdD8XRm9VyCYcp4qPHXNtrSj5ePEsSHyIG3H KmeNnd8hR9ztC1FAZ++3Dwu5edNSRFuXTWwWqTeIA== Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.appoci.oracle.com [130.35.103.27]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 4cr52t83rp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 06 Mar 2026 20:45:54 +0000 (GMT) Received: from pps.filterd (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 626J6Ecl023114; Fri, 6 Mar 2026 20:45:53 GMT Received: from pps.reinject (localhost [127.0.0.1]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 4ckptkey23-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 06 Mar 2026 20:45:53 +0000 Received: from iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 626Kjq8Z033939; Fri, 6 Mar 2026 20:45:53 GMT Received: from localhost.localdomain (ca-dev60.us.oracle.com [10.129.136.27]) by iadpaimrmta03.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 4ckptkey1q-1; Fri, 06 Mar 2026 20:45:52 +0000 From: Anthony Yznaga To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, david@kernel.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, jannh@google.com, pfalcato@suse.de, Jason@zx2c4.com Subject: [PATCH] mm: prevent droppable mappings from being locked Date: Fri, 6 Mar 2026 12:45:50 -0800 Message-ID: <20260306204550.8405-1-anthony.yznaga@oracle.com> X-Mailer: git-send-email 2.47.3 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-03-06_05,2026-03-06_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 phishscore=0 malwarescore=0 bulkscore=0 adultscore=0 spamscore=0 mlxlogscore=999 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2602130000 definitions=main-2603060196 X-Proofpoint-GUID: dFzVRbpyflEp6yyhZLFUCeqYT-4ZbZDG X-Proofpoint-ORIG-GUID: dFzVRbpyflEp6yyhZLFUCeqYT-4ZbZDG X-Authority-Analysis: v=2.4 cv=PdfyRyhd c=1 sm=1 tr=0 ts=69ab3d02 b=1 cx=c_pps a=qoll8+KPOyaMroiJ2sR5sw==:117 a=qoll8+KPOyaMroiJ2sR5sw==:17 a=Yq5XynenixoA:10 a=VkNPw1HP01LnGYTKEx00:22 a=jiCTI4zE5U7BLdzWsZGv:22 a=o5oIOnhZENCTenyL_yNV:22 a=yPCof4ZbAAAA:8 a=QaRZ64KJlpYahcCkVoYA:9 cc=ntf awl=host:12267 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMzA2MDE5NiBTYWx0ZWRfX1fDcSd6JBS0I zXDdsdcxfXmgPvWqp3jDlLjntkUVBv/JbM/exqj9p09RA/yAshrfY0gyx8whUgBdLwMEWnh9788 1hIYypClloc1WA4pYS1u88e+tNWJGgHpB73hpceah4QOprhfZk0oFxDLBYMKAsbgKmtySXXfs1C cq2NbYOHMrHkmnBparPcHFJVcIve3hEOPTGEnbP21kAc1V3xK9RG9sJ2EUJJUYekw/QU4DBLfVN ncD77ylrowp+/XKBXZyYJA7QCxbGXPt5WYyPKorz84WAS1Q3wNF5jX98sAf7jDDpWEIaxx1xbFI DL/GBB2ySoENKH1K7xltjLtoJI0KnXk87O3DgXeeGUAEbn/ggCxR2A+8+MnpuysAKdq+HQ4QILg Qbi+LIr0BSix8gAiK4IPkZ71lce7lIA/EYsXh82UFCuIqOU2lbvO/h43uuBMD/2N2OEMGeJ5n65 bkWTDdaCW0bcIqt6oAr7KlQKNbrZfsEvbhAht4lE= X-Rspam-User: X-Rspamd-Queue-Id: D1693C0004 X-Rspamd-Server: rspam08 X-Stat-Signature: oj7kgam668omb949hxang5cgn9ys41jx X-HE-Tag: 1772829958-608796 X-HE-Meta: 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 JR+AXzM0 /E7yvPKMR53xbuGJk9Q/GDtl3uvVEaZMPlFfPvftHZ1tROW92jKJBsJ6J2iUsZbE/v/vvDdmbAaP30OsbcpJQ2YoaN564zghXrbj2gjQnk7LTT4d0Ej6BphJ9wMrrl+ZsfqshcRMmuUbc7TzC0q0tWgswvF9vmOaWJGxFF6zopGR/2iWxEccDQKll5OFCVg8HduKpvQDIqgBj1qGiokipMWwXn0N7CDwjjwzpLdn0wd7RrCgWoCTTts66qmGcR1No8LYGNQa8MpldUKgaCIUMfFI9nIsprWxG6Anvt9seIr6YEaVx2a2E2jWamQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Mappings created with MAP_DROPPABLE cannot be locked via mlock() due to the check in mlock_fixup(). However, they will be locked indirectly if they are created after mlockall(MCL_FUTURE). Fixes: 9651fcedf7b9 ("mm: add MAP_DROPPABLE for designating always lazily freeable mappings") Signed-off-by: Anthony Yznaga --- include/linux/mm.h | 3 +++ mm/mlock.c | 4 ++-- mm/vma.c | 2 +- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5be3d8a8f806..bb830574d112 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -574,6 +574,9 @@ enum { /* This mask represents all the VMA flag bits used by mlock */ #define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT) +/* This mask prevents VMAs from being mlock'd */ +#define VM_NO_MLOCK_MASK (VM_SPECIAL | VM_DROPPABLE) + /* These flags can be updated atomically via VMA/mmap read lock. */ #define VM_ATOMIC_SET_ALLOWED VM_MAYBE_GUARD diff --git a/mm/mlock.c b/mm/mlock.c index 2f699c3497a5..fd35c1e88c4c 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -472,9 +472,9 @@ static int mlock_fixup(struct vma_iterator *vmi, struct vm_area_struct *vma, int ret = 0; vm_flags_t oldflags = vma->vm_flags; - if (newflags == oldflags || (oldflags & VM_SPECIAL) || + if (newflags == oldflags || (oldflags & VM_NO_MLOCK_MASK) || is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm) || - vma_is_dax(vma) || vma_is_secretmem(vma) || (oldflags & VM_DROPPABLE)) + vma_is_dax(vma) || vma_is_secretmem(vma)) /* don't set VM_LOCKED or VM_LOCKONFAULT and don't count */ goto out; diff --git a/mm/vma.c b/mm/vma.c index be64f781a3aa..1334622e4a03 100644 --- a/mm/vma.c +++ b/mm/vma.c @@ -2589,7 +2589,7 @@ static void __mmap_complete(struct mmap_state *map, struct vm_area_struct *vma) vm_stat_account(mm, vma->vm_flags, map->pglen); if (vm_flags & VM_LOCKED) { - if ((vm_flags & VM_SPECIAL) || vma_is_dax(vma) || + if ((vm_flags & VM_NO_MLOCK_MASK) || vma_is_dax(vma) || is_vm_hugetlb_page(vma) || vma == get_gate_vma(mm)) vm_flags_clear(vma, VM_LOCKED_MASK); -- 2.47.3