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=-17.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, 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 3BCDBC5ACAE for ; Thu, 12 Sep 2019 02:31:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0F36821928 for ; Thu, 12 Sep 2019 02:31:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="mJDejJWU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729080AbfILCbV (ORCPT ); Wed, 11 Sep 2019 22:31:21 -0400 Received: from mail-yw1-f73.google.com ([209.85.161.73]:44685 "EHLO mail-yw1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727477AbfILCbU (ORCPT ); Wed, 11 Sep 2019 22:31:20 -0400 Received: by mail-yw1-f73.google.com with SMTP id n3so19677594ywh.11 for ; Wed, 11 Sep 2019 19:31:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=VTFLG8eFeKeX5rA9A/RF+SH0kKZbbcZcTGiLOknhM8o=; b=mJDejJWULbF2e6+PZwAkN+YGqXTd60leJIfoP5qWwNzJgFkWguAYWTXbJHoH179vfN MNo0gETMkGUgE9ahWgfnQnCguxv1zyWyfPQ2DrDntXMldyLa/Eo2kA3/Uq3jteAPcB55 nTHNFlL0yZ/2vjoKxpDKIwjz1eYcjWO8Lf3MSwzODBLqcW4yQhjRRDjxezY2S4aWPYGy xHY7O/sD6nsAljyk2+jSMl+/UwCn8y3E9kB9WBwDIk9tP0gLmlthNDbAH9+ML/wDsIgQ EidIO4tIrVes2jrRn+rlnMICcIwA3NOOhfV+FnqdnFh1yhMGwgu7Mfk8vPa0cj1OJJTB AYhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=VTFLG8eFeKeX5rA9A/RF+SH0kKZbbcZcTGiLOknhM8o=; b=ohD0vOpzok7rmiyTL7W0urhZ1a7ocofcUZ0foyOu0rD7UaRgaf1ZbyUu9G3YB+Zppn eOG2ICYeT2P+DQmgMJeApIxEl3r9AhdQL3QJQ0pKbc8mN/XC1AoaK+0ziDYlD4xfgjTd OYFBFcQjFw/tZ99PlMPgK9cFLO8eAtaiDWFHp0+5FPSgneD3RGZD33YSrIKZaMWUERQx Xamw4B0HQIsd5lWDMc0wHjNTaw9AkDGM0vwuHdmlbIlBp11e5m3FckTq0oSTiKpfO0b/ w7129pj1aOV0LkP+qbmo0iXRrmPJd6wWm+HMR7V3Us+HWspIrk4JbAtOQJFCG6EPxbok /7gA== X-Gm-Message-State: APjAAAUQqVlPKI7So4/Rpm1tBMuYUkD1KZVAg8RFRgmYlOMhGxi/mMfV FhMr/dikpa0kHrGdUViWRsHQ/iRjVRg= X-Google-Smtp-Source: APXvYqwFp1R2W1Gg2Sjd02Xx4oKgaWAgWIlzHHZq+eTFExQ7YKzFQaF9vo3upTYjh4PTecTa61D2xskYkN4= X-Received: by 2002:a81:4e8d:: with SMTP id c135mr28278227ywb.149.1568255478967; Wed, 11 Sep 2019 19:31:18 -0700 (PDT) Date: Wed, 11 Sep 2019 20:31:11 -0600 In-Reply-To: <20190912023111.219636-1-yuzhao@google.com> Message-Id: <20190912023111.219636-4-yuzhao@google.com> Mime-Version: 1.0 References: <20190912004401.jdemtajrspetk3fh@box> <20190912023111.219636-1-yuzhao@google.com> X-Mailer: git-send-email 2.23.0.162.g0b9fbb3734-goog Subject: [PATCH v2 4/4] mm: lock slub page when listing objects From: Yu Zhao To: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , "Kirill A . Shutemov" , Tetsuo Handa Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yu Zhao Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Though I have no idea what the side effect of such race would be, apparently we want to prevent the free list from being changed while debugging the objects. Signed-off-by: Yu Zhao --- mm/slub.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/slub.c b/mm/slub.c index baa60dd73942..1c9726c28f0b 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4608,11 +4608,15 @@ static void process_slab(struct loc_track *t, struct kmem_cache *s, void *p; unsigned long *map; + slab_lock(page); + map = get_map(s, page); for_each_object(p, s, addr, page->objects) if (!test_bit(slab_index(p, s, addr), map)) add_location(t, s, get_track(s, p, alloc)); put_map(map); + + slab_unlock(page); } static int list_locations(struct kmem_cache *s, char *buf, -- 2.23.0.162.g0b9fbb3734-goog