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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 C33CCC433B4 for ; Fri, 21 May 2021 04:43:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93AFD613B4 for ; Fri, 21 May 2021 04:43:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239175AbhEUEpL (ORCPT ); Fri, 21 May 2021 00:45:11 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:40988 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S239172AbhEUEpL (ORCPT ); Fri, 21 May 2021 00:45:11 -0400 Received: from callcc.thunk.org (c-73-8-226-230.hsd1.il.comcast.net [73.8.226.230]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 14L4hh8u023398 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 21 May 2021 00:43:45 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 18B91420119; Fri, 21 May 2021 00:43:43 -0400 (EDT) Date: Fri, 21 May 2021 00:43:42 -0400 From: "Theodore Y. Ts'o" To: Alexey Makhalov Cc: linux-ext4@vger.kernel.org, stable@vger.kernel.org, Andreas Dilger Subject: Re: [PATCH] ext4: fix memory leak in ext4_fill_super Message-ID: References: <20210428221928.38960-1-amakhalov@vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210428221928.38960-1-amakhalov@vmware.com> Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed, Apr 28, 2021 at 10:19:28PM +0000, Alexey Makhalov wrote: > I've recently discovered that doing infinite loop of > systemctl start .mount, and > systemctl stop .mount > linearly increases percpu allocator memory consumption. > In several hours, it might lead to system instability by > consuming most of the memory. > > Bug is not reproducible when the ext4 filesystem is on > physical partition, but it is persistent when ext4 is on > logical volume. Why is this the case? It sounds like we're looking a buffer for each mount where the block size is not 1k. It shouldn't matter whether it is a physical partition or not. - Ted