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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17B54C433EF for ; Sat, 20 Nov 2021 22:11:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234714AbhKTWOX (ORCPT ); Sat, 20 Nov 2021 17:14:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234536AbhKTWOW (ORCPT ); Sat, 20 Nov 2021 17:14:22 -0500 Received: from mail-qk1-x72f.google.com (mail-qk1-x72f.google.com [IPv6:2607:f8b0:4864:20::72f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D95BC061574 for ; Sat, 20 Nov 2021 14:11:19 -0800 (PST) Received: by mail-qk1-x72f.google.com with SMTP id g28so13966865qkk.9 for ; Sat, 20 Nov 2021 14:11:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=RyCv7/k8cSIz9Mh5xeBnCG4BeWKtjmIRK1J+L90k8po=; b=V8bcQn7Wvp6gwbKSfpvD6QUr8L8jdiA3dp23dd7k7aOVyPba0mQXXsYrTrIInE5uuM MfU4BcD9b64YlK5JQ/Ow2qNU8YvLF1xDpL0efEJmP7c7XLD801msTbSPt/VWbUxoTPLv H0AuDloCsgA/00vVLVri9MODU6f5QVHDg1yjvCERKiAZbcd0jJFv/+7JwIETzAtJTlXx o0p2E7OUcZ2o9+tgrCjM9I/DW8g9+S7d2+jSD3tVBm8q5g4riicBpR5Q/DG2FCJlKJRB 7EbmqvABr2UL11UhvZDZD/CjEHIrGwkzIqvtcr91WYkVR+0suKkGz73+KGYz4oii6jo5 t7CA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=RyCv7/k8cSIz9Mh5xeBnCG4BeWKtjmIRK1J+L90k8po=; b=jTXod/O9kpuyva+YsGfiQumlxvWxSq8yhYa52CRnMMc2r8WtLTORYwIrQyGe4DGCHu sWUCKGf8WzssYALH0/Bc5Okv5FrzGqsfIrUOQ0CIsOdD5K7T/M82AM0karpISKyZ39Di F9fI+tbslPrR9hJbYydQPIDglKuwhCU31W7R0hU7fKsSHxGzi2tAZFGrHrpg5RHX6bN2 tUZyFnHmpMz1yfPfqTJMaRbTTXYtTGt+jPDkC2jOdCQ6Tqb3xZVNtOjaXsBdOkKGj7KX 5tllo7ck1yJrrwWVZ4y1mlurLXjFXiU8hCzgLF+FK2wuKBP4CDZ6oFTSTrSUS0c5eSPg Eysw== X-Gm-Message-State: AOAM531LKLdpkIBcrrjdykCRm+P/kz9xj/1WG+4HhF9gwQsGF1I3i0co TruNX09uyPiZswW7OA+TZzIdPPJQ6t1sVw== X-Google-Smtp-Source: ABdhPJxrlTMCykF9IYDAVbfFk+BohGWADP1E6JKl4yVIdeYgz66rrzXnl7y9buBmsQiwDDBww65Dtw== X-Received: by 2002:a05:620a:2447:: with SMTP id h7mr13966157qkn.75.1637446278061; Sat, 20 Nov 2021 14:11:18 -0800 (PST) Received: from localhost (cpe-174-109-172-136.nc.res.rr.com. [174.109.172.136]) by smtp.gmail.com with ESMTPSA id n19sm2030548qta.78.2021.11.20.14.11.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 20 Nov 2021 14:11:17 -0800 (PST) Date: Sat, 20 Nov 2021 17:11:16 -0500 From: Josef Bacik To: Qu Wenruo Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH] btrfs: fix the memory leak caused in lzo_compress_pages() Message-ID: References: <20211120083411.120338-1-wqu@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211120083411.120338-1-wqu@suse.com> Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Sat, Nov 20, 2021 at 04:34:11PM +0800, Qu Wenruo wrote: > [BUG] > Fstests generic/027 is pretty easy to trigger a slow but steady memory > leak if run with "-o compress=lzo" mount option. > > Normally one single run of generic/027 is enough to eat up at least 4G ram. > > [CAUSE] > In commit d4088803f511 ("btrfs: subpage: make lzo_compress_pages() > compatible") we changed how @page_in is released. > > But that refactor makes @page_in only released after all pages being > compressed. > > This leaves error path not releasing @page_in. And by "error path" > things like incompressible data will also be treated as an error > (-E2BIG). > > Thus it can leave btrfs to leak memory even there is nothing wrong > happened. > > [FIX] > Add check under @out label to release @page_in when needed, so when we > hit any error, the input page is properly released. > > Reported-by: Josef Bacik > Fixes: d4088803f511 ("btrfs: subpage: make lzo_compress_pages() compatible") > Signed-off-by: Qu Wenruo Woo now we're making it all the way through the xfstests runs on the vm that has -o compress=lzo. You can add Reviewed-and-tested-by: Josef Bacik Thanks for digging into this Qu, Josef