From nobody Tue Apr 7 10:38:51 2026 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 2A21EECAAD2 for ; Mon, 29 Aug 2022 21:26:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229730AbiH2V00 (ORCPT ); Mon, 29 Aug 2022 17:26:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229800AbiH2V0K (ORCPT ); Mon, 29 Aug 2022 17:26:10 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DF4870E60 for ; Mon, 29 Aug 2022 14:25:49 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id x8-20020a17090a1f8800b001faa9857ef2so3894749pja.0 for ; Mon, 29 Aug 2022 14:25:48 -0700 (PDT) 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; bh=knlkft8CSs4ctk+Wf5EGoFcT9IapAOL4+B6Ai/+T1Ew=; b=P37RAGhPa0fj1eu5oWQ75AvAaLtugohQsYRWKzKsYPy82nTGbYS2huH/UiZNVvoE/s 88nyZ5hMCHsleX96EzwxSRzBq/7CUKc/bHbJ31Ts1GLCvmDOU9CmcQD2WQXDTk1c+h7j 3oIUBNbln4Bxomo0AKLbatKVQNVrzgPz+A4aQoGdDS5LbHfkkFmAcE6pV6uk/ymeBjbJ 1nc4oAeG1urj8/jUSameTDeH8ziLxBTZVHP9LQuagPlJAxjluMekWoC6NIdC1YJBWEbt nn2+QyaYYhDKNwmBnD8p146GgfwAnKteHIAkGMz5qwPGMxUQt1Cd0qMSAU4DAqNB0mVB aVgw== 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; bh=knlkft8CSs4ctk+Wf5EGoFcT9IapAOL4+B6Ai/+T1Ew=; b=hY5S5bMd/JZYq9RE32ihPedbkWPG7PCCRMym9mdGI4Uci7RTcqJtbERTxylkmtSKF8 WAR3wklTTrgWrQ4fzg6N30Zqe72kLTpEUtQff3Yne/0pl6wCVhmW8yMaAlBlHrLxuBf/ PYGkNypsAN8cgshtSA7Cscn4U3VIu6sYrYABkUclXKn0gYgtCmh4c98tYkYMdhwaMriT e/EbWSm1mSftx9rzPhlJMf0r2XqBd1+lK5S6AZ8UpX80d7+g1K9lqIysRefdxPa3ftv4 +/2e+RzS1rh8BJo11Cd2F8uUYiU0fikYuBT/tllcWYTh3Z/Oo1BhrpCt29M11VohPhLp 0kXA== X-Gm-Message-State: ACgBeo2g4G0mfzNvDld+iHgc23k7Nv3Rb3cmh84MNGym5QCFX6CJOu7x 8MFfXlT4sY5lhnaz6HhkDeWEye179Tc= X-Google-Smtp-Source: AA6agR7ucJtBhSAnuB+PqV9qzppZFKeEkxBUzS6um9UDd2r/XYBs5DAVo1iLh4VL9E0CKz9mlSvmLd+h5RQ= X-Received: from surenb-spec.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e30]) (user=surenb job=sendgmr) by 2002:aa7:8d08:0:b0:538:105a:eb6a with SMTP id j8-20020aa78d08000000b00538105aeb6amr10112054pfe.42.1661808348114; Mon, 29 Aug 2022 14:25:48 -0700 (PDT) Date: Mon, 29 Aug 2022 21:25:10 +0000 In-Reply-To: <20220829212531.3184856-1-surenb@google.com> Mime-Version: 1.0 References: <20220829212531.3184856-1-surenb@google.com> X-Mailer: git-send-email 2.37.2.672.g94769d06f0-goog Message-ID: <20220829212531.3184856-8-surenb@google.com> Subject: [RFC PATCH 07/28] kernel/fork: mark VMAs as locked before copying pages during fork 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, laurent.dufour@fr.ibm.com, paulmck@kernel.org, riel@surriel.com, 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, rientjes@google.com, axelrasmussen@google.com, joelaf@google.com, minchan@google.com, surenb@google.com, kernel-team@android.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Protect VMAs from concurrent page fault handler while performing copy_page_range for VMAs having VM_WIPEONFORK flag set. Signed-off-by: Suren Baghdasaryan --- kernel/fork.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/fork.c b/kernel/fork.c index bfab31ecd11e..1872ad549fed 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -709,8 +709,10 @@ static __latent_entropy int dup_mmap(struct mm_struct = *mm, rb_parent =3D &tmp->vm_rb; =20 mm->map_count++; - if (!(tmp->vm_flags & VM_WIPEONFORK)) + if (!(tmp->vm_flags & VM_WIPEONFORK)) { + vma_mark_locked(mpnt); retval =3D copy_page_range(tmp, mpnt); + } =20 if (tmp->vm_ops && tmp->vm_ops->open) tmp->vm_ops->open(tmp); --=20 2.37.2.672.g94769d06f0-goog