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 X-Spam-Level: X-Spam-Status: No, score=-12.9 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0BA6C433DF for ; Thu, 21 May 2020 13:50:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C171A206B6 for ; Thu, 21 May 2020 13:50:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="kRdZ04hI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729581AbgEUNuM (ORCPT ); Thu, 21 May 2020 09:50:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729197AbgEUNuL (ORCPT ); Thu, 21 May 2020 09:50:11 -0400 Received: from mail-oi1-x242.google.com (mail-oi1-x242.google.com [IPv6:2607:f8b0:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82CFDC061A0E for ; Thu, 21 May 2020 06:50:11 -0700 (PDT) Received: by mail-oi1-x242.google.com with SMTP id y85so6205845oie.11 for ; Thu, 21 May 2020 06:50:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:user-agent:mime-version; bh=+rx34frGAhxyFDztnsG4UwVe/jVB01cbcYcfehMFKm8=; b=kRdZ04hIwcg5sBPK4ZhOUKQ/+STfLXkTdU84uMqlC08Tc2YPDWygXEH7X+YlXQLiJ1 9gvo9hHQo1liVi1sL/9l5aWnHUTFJo9laFK227tXIyQva+USV1GWzP5eDF0LeZ73cX1b rxUshQh//HagrZkGxp/e7RIGnDHRl/jDvkMN1G3P3uhAKYLTT9e2QXK29XMFV8FrOhoD 4d/ULAkAXoPNkDKJCyr8489YH3miJ5sAOeQUs4iLLxQDWbA+ltkCQDTItEN0GaUSWzS5 gawh9LukYIKnqmGkntX3ShtKxhORzdJVDObLxpu/VffC2Z3L1gKBxmX+LS0erxSK5BaR BX4g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:user-agent :mime-version; bh=+rx34frGAhxyFDztnsG4UwVe/jVB01cbcYcfehMFKm8=; b=iXWFFyKHoX/eepsFES/UK+KRXLwhyxhILEB9wb2bgSiQXj0Ur3kmAoKLYfJ78gWzOK ohZZ2T8xEMYTsufQeFUIzSKFsI7HAftxf0Ae1aSy6B8WbU1i1wRMctG1MtxRTeA5UkNi S9WLOKq7HMFRenSgvT4lRQfDb0gRz0aAR0QNptUGZe3jKezm3ndthN/a2mBdCWnM2N7y h/2b7QilQAHELbx0ah+Bokj4CCxrJfgQUA7UoqMjGwUXyfXyuypaJG5E9F4uNct2cHU/ ADtVHbDVUWYlpw6zz/s8ID4orc8nIrNC7ew13EH7BGLkyF/RlxKDro0URYCVf9YeRaM/ nkjA== X-Gm-Message-State: AOAM531maAr8vx81NRUrZxqL1r/nslRHxl7jcqTjfijhH8yasj83wZ/2 q6ahNaiBFbxLOKZ6Pf4zUBooUA== X-Google-Smtp-Source: ABdhPJyhaSNhjeHFlsDhzLGECwTxxbYZQS3ikIOsP8AocLiNXEM3A1jjJtyElbPfeZXokR8Vgsc16w== X-Received: by 2002:a54:4512:: with SMTP id l18mr6970406oil.81.1590069010565; Thu, 21 May 2020 06:50:10 -0700 (PDT) Received: from eggly.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id q16sm1599162ota.3.2020.05.21.06.50.08 (version=TLS1 cipher=ECDHE-ECDSA-AES128-SHA bits=128/128); Thu, 21 May 2020 06:50:09 -0700 (PDT) Date: Thu, 21 May 2020 06:49:51 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Andrew Morton cc: Anshuman Khandual , Naoya Horiguchi , Zi Yan , John Hubbard , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH mmotm] mm/vmstat: Add events for PMD based THP migration without split fix Message-ID: User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fix 5.7-rc6-mm1 page migration crash in unmap_and_move(): when the page to be migrated has been freed from under us, that is considered a MIGRATEPAGE_SUCCESS, but no newpage has been allocated (and I don't think it would ever need to be counted as a successful THP migration). Signed-off-by: Hugh Dickins --- Fix to mm-vmstat-add-events-for-pmd-based-thp-migration-without-split.patch mm/migrate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- 5.7-rc6-mm1/mm/migrate.c 2020-05-20 12:21:56.117693827 -0700 +++ linux/mm/migrate.c 2020-05-20 15:08:12.319476978 -0700 @@ -1248,7 +1248,7 @@ out: * we want to retry. */ if (rc == MIGRATEPAGE_SUCCESS) { - if (PageTransHuge(newpage)) + if (newpage && PageTransHuge(newpage)) thp_migration_success(true); put_page(page); if (reason == MR_MEMORY_FAILURE) {