Received: by 2002:ad5:474a:0:0:0:0:0 with SMTP id i10csp667561imu; Wed, 9 Jan 2019 04:30:23 -0800 (PST) X-Google-Smtp-Source: ALg8bN7RXnkEuT/UqY6VcMAc5feBkyJpMGpS1oNMoWLs4+EWdHodjM4lxF58hs1nmNoBohTzmbmh X-Received: by 2002:a62:c505:: with SMTP id j5mr5778149pfg.149.1547037023271; Wed, 09 Jan 2019 04:30:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1547037023; cv=none; d=google.com; s=arc-20160816; b=uSv6c1p+KTU/2uDEWSdjUdfiDwnVZPMKDO7kNSEIjfNoePUAhwOI4NDDb6S0jdxKvw jxC/wcMjqOPtU/u/vDGMRGarn6Q8J9hWQN8oB9Iz5jrbfrBi3nNt9z8JaEg+CvPmYIe5 md7PwFRV59FSn6WTAiIivWpeXoI3nThmy9eT8NFp4m9JPr4LAejngVFAqZuK0GhLRdSH FRkUoTzD04751F158mFKF1Mrzit0I4+mMuChRO2WWzWMjlTXJy3QM5hscOz8pQQgLlZA 9kHiDPy62C5X7ZHPnLDVWNtKF85d5ju3/xbETuVLmPXx1YY34Q+K1qQR+husuIxpMSQp jUaw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:dkim-signature; bh=MsqdlZbisRBCTK/NvhVywIGrWksr2rkv3CdCXPuM/Fw=; b=SReZLKulOFcqcpu78yGUtoW8ss6D5HaLAofnVbPHaRom/m/4wnjgoH6h9WgspRbsI3 dupa1cdu7Pl4vBraN5uKNJEaZZ4kIc8qo6gM4YCErYFgH7C5p14XVSlji6dAKndljIu9 oBFrkPHDnWQMxiztdjQ4CudPZakFJyaT6ZqSgqi+h2vW8a9L72WjZAYljwT8982VCof8 AC/mZkaPlhukXyY5mdXLt1x0fh+XjNOT84vq3CC4nDKKfhN2YYUXxHXa2DQbqRlyXJDu ppjxKClzNG/TzW6nJdtKkrtc0FLDrxMieKuwwXKw2ZSl3KIGg2PBGxsSI511RSOw9x3O VKuw== ARC-Authentication-Results: i=1; mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=m55UTsH9; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id p10si3679320pgi.549.2019.01.09.04.30.07; Wed, 09 Jan 2019 04:30:23 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@infradead.org header.s=bombadil.20170209 header.b=m55UTsH9; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730694AbfAIMOC (ORCPT + 99 others); Wed, 9 Jan 2019 07:14:02 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:33106 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730481AbfAIMOB (ORCPT ); Wed, 9 Jan 2019 07:14:01 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=MsqdlZbisRBCTK/NvhVywIGrWksr2rkv3CdCXPuM/Fw=; b=m55UTsH9qk0hZQ+xVTu9VijX5 MM5aQjug4xoknDeD13TH3vy4yXPZIbhCAkmxUk2tQTZlzZJiBL2J9lWdywZt+7lu9ikxsUi0G7dyV P1uNY3Z2wFIAgSVABFnHTg89BFN488+vmIEeaSXqkzoUFLmTpQgqrVDVx0esVCkLmPESyAdthMX74 n6KLaE+RsQgz4O+hfBD63JainCpTagOATsBx171qclXkyYFat8H2QPFlOKt10E0duEh31BOTBNiVu D000dTzKIeyJLHeNlxuNsPJQWLBbVWqUxdz2DpWn3PXTUF+ykGLSEeZLophOBUJmRT5y9jUmREa6L E24lJ6EpQ==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1ghCk4-0006Yz-Uw; Wed, 09 Jan 2019 12:13:52 +0000 Date: Wed, 9 Jan 2019 04:13:52 -0800 From: Matthew Wilcox To: Peng Wang Cc: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/slub.c: re-randomize random_seq if necessary Message-ID: <20190109121352.GI6310@bombadil.infradead.org> References: <20190109090628.1695-1-rocking@whu.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190109090628.1695-1-rocking@whu.edu.cn> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 09, 2019 at 05:06:27PM +0800, Peng Wang wrote: > calculate_sizes() could be called in several places > like (red_zone/poison/order/store_user)_store() while > random_seq remains unchanged. > > If random_seq is not NULL in calculate_sizes(), re-randomize it. Why do we want to re-randomise the slab at these points?