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 903EBC3A5A4 for ; Mon, 26 Aug 2019 05:13:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2EC812080C for ; Mon, 26 Aug 2019 05:13:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="K1dR2BTg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EC812080C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 97A7F6B0524; Mon, 26 Aug 2019 01:13:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 92C506B0525; Mon, 26 Aug 2019 01:13:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 841436B0526; Mon, 26 Aug 2019 01:13:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0156.hostedemail.com [216.40.44.156]) by kanga.kvack.org (Postfix) with ESMTP id 641736B0524 for ; Mon, 26 Aug 2019 01:13:47 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id E064252AA for ; Mon, 26 Aug 2019 05:13:46 +0000 (UTC) X-FDA: 75863411652.15.ghost97_3e0f214173b54 X-HE-Tag: ghost97_3e0f214173b54 X-Filterd-Recvd-Size: 4183 Received: from mail-pg1-f193.google.com (mail-pg1-f193.google.com [209.85.215.193]) by imf35.hostedemail.com (Postfix) with ESMTP for ; Mon, 26 Aug 2019 05:13:46 +0000 (UTC) Received: by mail-pg1-f193.google.com with SMTP id d1so9841095pgp.4 for ; Sun, 25 Aug 2019 22:13:46 -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=pebLW56jCi7VjFqP9h+fFUJtdRnB0Y6W1USo0gofePFJk8Ps/je6R+djIYFXZskkxW jzF8LzcP6tPRE6Tr2n82Sxowy5EuP1x3FnBjUhZf44yFrSPnBBHyNnlrjxS7VIEZM7vZ sNlRJ54711d7WdXe31azyiUzezGqJ4M34eXxZ4zEhKDTtEjEDnM95DT/xCuCFH7WXCdZ gWWEujRgyzfSXtZYVhEJ2WKaNW+OErMWkYMamG+EsHAN5fOGbzi67JdQ62hiZHEKVIYQ p65pvuXnsFlySKQBbgKCoVRto/58vea3VMl/fZAROXyJpnpsllNpSZOnU2eHd8q8BkMF P78A== X-Gm-Message-State: APjAAAVx4jI0w2YCh5/3nL1LcrAvEdv7nc6bJ/aR9W+tHOx8z70KJ8eK PlX0cd+cEA5mvO7KTe88w4Sqxta0 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) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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