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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 E4E1FC3A59E for ; Mon, 26 Aug 2019 05:13:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B12162080C for ; Mon, 26 Aug 2019 05:13:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="K1dR2BTg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729217AbfHZFNq (ORCPT ); Mon, 26 Aug 2019 01:13:46 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:34917 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725446AbfHZFNq (ORCPT ); Mon, 26 Aug 2019 01:13:46 -0400 Received: by mail-pg1-f193.google.com with SMTP id n4so9854677pgv.2 for ; Sun, 25 Aug 2019 22:13:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=RS54P8xWhN0WpqilfX3CeJTlw03oZ0bA+FF2sB+7VdE=; b=K1dR2BTgQvrbOF9jRsFWIkPFShaGlCPz35NWloS4Fv+m6/EhuR6r9hhY22ZCmXh9nw kMho4xHr1YYm9HYipqrdH03DaX8Y5T8ABJFwn/Bj5djDVplrze3YMP/rRJnYQBK3agjz j/2nMTQ1ibl/XU4niUZX34IsaSjsYMktRp+9VB+fmx/e741XRl+bh+v5TNaAg/uaYOyr rl+5noSQB64GhX2EutHURwwC1CTdpokKQLJ9YugJw0VkZNuI3DUpH0F3NQKM0T7eZvTA FT43OfyGLj7Ip10kVzPL9y+Mx6HJL+s1iQgTZy/qAX5MLtmk9pF2d3XkJyFBVEO4shaa PqJg== 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:references :mime-version:content-disposition:in-reply-to:user-agent; bh=RS54P8xWhN0WpqilfX3CeJTlw03oZ0bA+FF2sB+7VdE=; b=E3TYLIoJ9BZjAMV90VnWXmzepzgXwGo7peXseODlFV+DHDiN/F2eJRVrFpptMgLwL1 6PH9n+/4fxs187XV+sMl8al7gCGZTj7BYBns9hwbdMvP1i0v6RrYMjbaGuAzgIriuhoa DijUcXdXcSEM/BA9STFwtGLpVLM/RVjeUqJ4AMGY396rAbOfU8NxxVbcsLLBjYfMI7Fx 0tSfqXFigY5JDI815NqajL69NNO6DvqU93/gF8XpI4xWoBi3gcalOqFkek0A+CDGFpQA ZRrsZvV5oNeJPqPwa2Ekywp7/Ot6jsADcy16sGgdJP/fM86FP3zlsiZEs/cbGUEeISpK mYDg== X-Gm-Message-State: APjAAAVnjd6+JIU2UwGtbvatcZ9kzAJZkioi/HSE/J8qQm4iz1icsuCU HX0XO8aniEykbHgtXHdJmrU= X-Google-Smtp-Source: APXvYqzsH1YZgcoQJAmfj/sq9jg7AkDH4XHU8wEYr6A3wUzKAcmf0uIlpnUP9bwKVzxF7h8VFXxPfA== X-Received: by 2002:a62:8745:: with SMTP id i66mr17899570pfe.259.1566796425463; Sun, 25 Aug 2019 22:13:45 -0700 (PDT) Received: from localhost ([110.70.50.154]) by smtp.gmail.com with ESMTPSA id r4sm10753832pfl.127.2019.08.25.22.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Aug 2019 22:13:44 -0700 (PDT) Date: Mon, 26 Aug 2019 14:13:40 +0900 From: Sergey Senozhatsky To: Henry Burns Cc: Andrew Morton , Sergey Senozhatsky , Henry Burns , Minchan Kim , Nitin Gupta , Shakeel Butt , Jonathan Adams , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2 v2] mm/zsmalloc.c: Fix race condition in zs_destroy_pool Message-ID: <20190826051340.GA26785@jagdpanzerIV> References: <20190809181751.219326-1-henryburns@google.com> <20190809181751.219326-2-henryburns@google.com> <20190820025939.GD500@jagdpanzerIV> <20190822162302.6fdda379ada876e46a14a51e@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (08/23/19 04:10), Henry Burns wrote: > > Thanks. So we have a couple of races which result in memory leaks? Do > > we feel this is serious enough to justify a -stable backport of the > > fixes? > > In this case a memory leak could lead to an eventual crash if > compaction hits the leaked page. I don't know what a -stable > backport entails, but this crash would only occur if people are > changing their zswap backend at runtime > (which eventually starts destruction). Well, zram/zsmalloc is not only for swapping, but it's also a virtual block device which can be created or destroyed dynamically. So it looks like a potential -stable material. Minchan? -ss