From nobody Thu Nov 14 06:54:28 2024 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C2EAC54EAA for ; Thu, 26 Jan 2023 19:38:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232604AbjAZTiq (ORCPT ); Thu, 26 Jan 2023 14:38:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232505AbjAZTiL (ORCPT ); Thu, 26 Jan 2023 14:38:11 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DB2A402DA for ; Thu, 26 Jan 2023 11:38:09 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id w70-20020a25df49000000b00803e799d7b1so2976685ybg.10 for ; Thu, 26 Jan 2023 11:38:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=7SychSIO4sUWIo6QruxirbFjx5CbYNnUeHZ00ltQsQk=; b=Pfx+wzAhZ6kKsJzDDedQ8LJwSdqFciZXcllolwp4vBQ+2oIO3zY1GANQzoJfCZWzvE CQPh21a5oWziH93KMEhfcmcYLI66KcWMq+wv9dH36RAXDaWDj3mhxF37O3hO+Nm3j333 DQpz5N93q63IgXjq4N824biP5tt/Btbtpk79Xp1oY2XkCbJniy2hm75eubONJlrUyJHz 4nhnfw5vwu2MM7c8JHS86kwr5IkxCGiAvk+B0fbplC2co4C0HnFTpw4esf89gAkAXtE3 btQ+U4BHBe8XCXeuy8OqZ9E2kM4KncMQmpjGCBcfb2U1tiWjIaGyYCULw+IAQrOfXIUP +Htg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=7SychSIO4sUWIo6QruxirbFjx5CbYNnUeHZ00ltQsQk=; b=WK3CZIeRLI+fSss2z01j4gNLHPk1qm/pwEiQ5dckmCYGBg2TgmpkFOXNp45lWM2GNq ub8s6HK95jEOhAKYP4PO2fh+Zp50HQnYy2eE1xT267UrXXBOuD9dUZU6BHiUNM3AaqAX u8ILVSmv7o1+gXirQpg1y2vaPjyiADTOBgDVTCyVFLy11yOW6WvO1KVGNjNIA85+EAmA U6SFcDeOjM3VQLM0A++6njcjle6So/wcZ61JBhkTNUDIXcslANAJae80iKt+RW1z4Bch y/OEVvnOxLa0z/V3q1m2nRuvxe50WU+Qj6kik70E6iGWVZIoDJ2gz96Ow7s657rCiKVu /Jeg== X-Gm-Message-State: AFqh2kqERfUIDbPgrcGOEZMgpSGu3GufKSbF2ajFo4j+oi6afmnKlMkR bLLG1BTpPI90C6+90vVJAa+Obme0y5s= X-Google-Smtp-Source: AMrXdXsXS6jvs2FLo8wLjzpNR7510A/NF2577gEg88y5p+yBM43aas9S20uDvZYfhxK8qIb0YJZmeRS9JA0= X-Received: from surenb-desktop.mtv.corp.google.com ([2620:15c:211:200:d774:88af:bab3:648d]) (user=surenb job=sendgmr) by 2002:a5b:2ca:0:b0:7d2:d238:42b4 with SMTP id h10-20020a5b02ca000000b007d2d23842b4mr3963873ybp.526.1674761888262; Thu, 26 Jan 2023 11:38:08 -0800 (PST) Date: Thu, 26 Jan 2023 11:37:50 -0800 In-Reply-To: <20230126193752.297968-1-surenb@google.com> Mime-Version: 1.0 References: <20230126193752.297968-1-surenb@google.com> X-Mailer: git-send-email 2.39.1.456.gfc5497dd1b-goog Message-ID: <20230126193752.297968-6-surenb@google.com> Subject: [PATCH v4 5/7] mm: replace vma->vm_flags indirect modification in ksm_madvise From: Suren Baghdasaryan To: akpm@linux-foundation.org Cc: michel@lespinasse.org, jglisse@google.com, mhocko@suse.com, vbabka@suse.cz, hannes@cmpxchg.org, mgorman@techsingularity.net, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, peterz@infradead.org, ldufour@linux.ibm.com, paulmck@kernel.org, mingo@redhat.com, will@kernel.org, luto@kernel.org, songliubraving@fb.com, peterx@redhat.com, david@redhat.com, dhowells@redhat.com, hughd@google.com, bigeasy@linutronix.de, kent.overstreet@linux.dev, punit.agrawal@bytedance.com, lstoakes@gmail.com, peterjung1337@gmail.com, rientjes@google.com, axelrasmussen@google.com, joelaf@google.com, minchan@google.com, rppt@kernel.org, jannh@google.com, shakeelb@google.com, tatashin@google.com, edumazet@google.com, gthelen@google.com, gurua@google.com, arjunroy@google.com, soheil@google.com, leewalsh@google.com, posk@google.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, linux-kernel@vger.kernel.org, kernel-team@android.com, surenb@google.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Replace indirect modifications to vma->vm_flags with calls to modifier functions to be able to track flag changes and to keep vma locking correctness. Signed-off-by: Suren Baghdasaryan Acked-by: Michal Hocko Acked-by: Mel Gorman Acked-by: Mike Rapoport (IBM) Acked-by: Michael Ellerman (powerpc) Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> --- arch/powerpc/kvm/book3s_hv_uvmem.c | 6 +++++- arch/s390/mm/gmap.c | 6 +++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_h= v_uvmem.c index 1d67baa5557a..709ebd578394 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -393,6 +393,7 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm, { unsigned long gfn =3D memslot->base_gfn; unsigned long end, start =3D gfn_to_hva(kvm, gfn); + unsigned long vm_flags; int ret =3D 0; struct vm_area_struct *vma; int merge_flag =3D (merge) ? MADV_MERGEABLE : MADV_UNMERGEABLE; @@ -409,12 +410,15 @@ static int kvmppc_memslot_page_merge(struct kvm *kvm, ret =3D H_STATE; break; } + /* Copy vm_flags to avoid partial modifications in ksm_madvise */ + vm_flags =3D vma->vm_flags; ret =3D ksm_madvise(vma, vma->vm_start, vma->vm_end, - merge_flag, &vma->vm_flags); + merge_flag, &vm_flags); if (ret) { ret =3D H_STATE; break; } + vm_flags_reset(vma, vm_flags); start =3D vma->vm_end; } while (end > vma->vm_end); =20 diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index ab836597419d..5a716bdcba05 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2587,14 +2587,18 @@ int gmap_mark_unmergeable(void) { struct mm_struct *mm =3D current->mm; struct vm_area_struct *vma; + unsigned long vm_flags; int ret; VMA_ITERATOR(vmi, mm, 0); =20 for_each_vma(vmi, vma) { + /* Copy vm_flags to avoid partial modifications in ksm_madvise */ + vm_flags =3D vma->vm_flags; ret =3D ksm_madvise(vma, vma->vm_start, vma->vm_end, - MADV_UNMERGEABLE, &vma->vm_flags); + MADV_UNMERGEABLE, &vm_flags); if (ret) return ret; + vm_flags_reset(vma, vm_flags); } mm->def_flags &=3D ~VM_MERGEABLE; return 0; --=20 2.39.1