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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 49452C636C9 for ; Wed, 21 Jul 2021 13:09:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2487661029 for ; Wed, 21 Jul 2021 13:09:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231139AbhGUM2e (ORCPT ); Wed, 21 Jul 2021 08:28:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232456AbhGUM1o (ORCPT ); Wed, 21 Jul 2021 08:27:44 -0400 Received: from mail-vs1-xe32.google.com (mail-vs1-xe32.google.com [IPv6:2607:f8b0:4864:20::e32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72593C061574 for ; Wed, 21 Jul 2021 06:08:21 -0700 (PDT) Received: by mail-vs1-xe32.google.com with SMTP id f4so1365998vsh.11 for ; Wed, 21 Jul 2021 06:08:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Dt9aDr0YJ9OipK4M1aA2G+MpBHasElMd5/QYQDX4pXQ=; b=jfgYg2DauwNXLT98x1VyAzN3sZmfwHyxfxfxug+2/RWvktHDGzfABdvVZC1pVkGiJM jUa0SNIgACnNw8TLozBrcnF1evIBSK8PM7Wzp0LRWbw9nhJwmPV07CBm/4QTAkV9BLFH lhrDeKOj5fXRu3JOSdRpNcAnI6LyBYqowumME= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Dt9aDr0YJ9OipK4M1aA2G+MpBHasElMd5/QYQDX4pXQ=; b=UbxzONpLWTVpa05oYTIQBrPL8w+ES5s7piJ5C1pdFO+tabTX51vQO24m6PecXYep2L rY3fICYbsto5mGvw9I0zjMxfEkZdcQFgUghZWIz1KmV8qVx/zeOllKjY+oEMmClA23nV qrenWJKad9/Q3mioVHGE8Y9DhpLSgmCXOPaOq3QfR9C+tO5kXID5QiJ3NaTnVKmcCoqB M0FH4fCKPJNqZF7IwB93+3Ner66R5mb1jiEGG1RNYRoOQB+g/h5KMXaVtwJLYx9/wsP1 jN5iS0aBKTZebxKhBptYR7QF6ybLI1+V2mFIypzkTYE2GFYwcEYzg+FxrM5pk/Br19jU x0QQ== X-Gm-Message-State: AOAM530q4fqUF9uLNAZ0cpEKOMMgoATB0z9pBMk8Qlah7QUxXqJJA/pe yXoO/Uc8LhcfRm+B5VJc2ypbT2Ph281rfjbPw+fDZw== X-Google-Smtp-Source: ABdhPJyqxSeaX+uDdhtw7EKkRvfT1t32hb+2dwJWqPv+Mg8ei4nzS3QAk7F7TmMVUeyK1VPMFEHtYMvVHHOOeRNtDzg= X-Received: by 2002:a05:6102:2143:: with SMTP id h3mr30756362vsg.9.1626872898079; Wed, 21 Jul 2021 06:08:18 -0700 (PDT) MIME-Version: 1.0 References: <20210426152021.1145298-1-amir73il@gmail.com> In-Reply-To: From: Miklos Szeredi Date: Wed, 21 Jul 2021 15:08:07 +0200 Message-ID: Subject: Re: [PATCH] ovl: skip stale entries in merge dir cache iteration To: Amir Goldstein Cc: overlayfs , Eryu Guan Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org On Tue, 20 Jul 2021 at 18:17, Amir Goldstein wrote: > > On Tue, Jul 20, 2021 at 5:55 PM Amir Goldstein wrote: > > > > On Tue, Jul 20, 2021 at 10:18 AM Amir Goldstein wrote: > > > > > > On Tue, Jul 20, 2021 at 7:22 AM Miklos Szeredi wrote: > > > > > > > > On Tue, 20 Jul 2021 at 06:19, Miklos Szeredi wrote: > > > > > > > > > > On Mon, 19 Jul 2021 at 18:43, Amir Goldstein wrote: > > > > > > > > > > > > On Mon, Jul 19, 2021 at 6:24 PM Miklos Szeredi wrote: > > > > > > > > > > > > > > On Fri, 4 Jun 2021 at 12:43, Amir Goldstein wrote: > > > > > > > > > > > > > > > > On Mon, Apr 26, 2021 at 6:20 PM Amir Goldstein wrote: > > > > > > > > > > > > > > > > > > On the first getdents call, ovl_iterate() populates the readdir cache > > > > > > > > > with a list of entries, but for upper entries with origin lower inode, > > > > > > > > > p->ino remains zero. > > > > > > > > > > > > > > > > > > Following getdents calls traverse the readdir cache list and call > > > > > > > > > ovl_cache_update_ino() for entries with zero p->ino to lookup the entry > > > > > > > > > in the overlay and return d_ino that is consistent with st_ino. > > > > > > > > > > > > > > > > > > If the upper file was unlinked between the first getdents call and the > > > > > > > > > getdents call that lists the file entry, ovl_cache_update_ino() will not > > > > > > > > > find the entry and fall back to setting d_ino to the upper real st_ino, > > > > > > > > > which is inconsistent with how this object was presented to users. > > > > > > > > > > > > > > > > > > Instead of listing a stale entry with inconsistent d_ino, simply skip > > > > > > > > > the stale entry, which is better for users. > > > > > > > > > > > > > > > > > > > > > > > > > Miklos, > > > > > > > > > > > > > > > > I forgot to follow up on this patch. > > > > > > > > Upstream xfstest overlay/077 is failing without this patch. > > > > > > > > > > > > > > Can't reproduce (on ext4/xfs and "-oxino=on"). > > > > > > > > > > > > > > Is there some trick? > > > > > > > > > > > > Not sure. overlay/077 fails for me on v5.14.0-rc2 on ext4/xfs. > > > > > > > > > > > > QA output created by 077 > > > > > > +entry m100 has inconsistent d_ino (234 != 232) > > > > > > +entry f100 has inconsistent d_ino (335 != 16777542) > > > > > > Silence is golden > > > > > > > > > > > > Maybe you need to build src/t_dir_offset2? > > > > > > > > > > root@kvm:/opt/xfstests-dev# git log -1 --pretty=%h > > > > > 10f6b231 > > > > > root@kvm:/opt/xfstests-dev# cat local.config > > > > > export TEST_DEV=/dev/vdb1 > > > > > export TEST_DIR=/test > > > > > export SCRATCH_DEV=/dev/vdb2 > > > > > export SCRATCH_MNT=/scratch > > > > > export FSTYP=ext4 > > > > > export OVERLAY_MOUNT_OPTIONS="-o xino=on" > > > > > root@kvm:/opt/xfstests-dev# make src/t_dir_offset2 > > > > > make: 'src/t_dir_offset2' is up to date. > > > > > root@kvm:/opt/xfstests-dev# ./check -overlay overlay/077 > > > > > FSTYP -- overlay > > > > > PLATFORM -- Linux/x86_64 kvm 5.14.0-rc2 #276 SMP Tue Jul 20 > > > > > 05:54:44 CEST 2021 > > > > > MKFS_OPTIONS -- /scratch > > > > > MOUNT_OPTIONS -- -o xino=on /scratch /scratch/ovl-mnt > > > > > > > > > > overlay/077 1s ... 1s > > > > > Ran: overlay/077 > > > > > Passed all 1 tests > > > > > > > > > > root@kvm:/opt/xfstests-dev# cat results/overlay/077.full > > > > > > > > > > Create file in pure upper dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > created entry p0 > > > > > entry p0 found as expected > > > > > > > > > > Remove file in pure upper dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > unlinked entry p100 > > > > > entry p100 not found as expected > > > > > > > > > > Create file in impure upper dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > created entry o0 > > > > > entry o0 found as expected > > > > > > > > > > Remove file in impure upper dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > unlinked entry o100 > > > > > entry o100 not found as expected > > > > > > > > > > Create file in merge dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > created entry m0 > > > > > entry m0 found as expected > > > > > > > > > > Remove file in merge dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > unlinked entry m100 > > > > > entry m100 not found as expected > > > > > > > > > > Create file in former merge dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > created entry f0 > > > > > entry f0 found as expected > > > > > > > > > > Remove file in former merge dir: > > > > > getdents at offset 0 returned 192 bytes > > > > > unlinked entry f100 > > > > > entry f100 not found as expected > > > > > > > > > > Ideas for further debugging why this test isn't failing for v4.12-rc2? > > > > > > > > > > It's not you, it's me ;-) > > > > > > The failure was lost during cleanup of t_dir_offset2 patches > > > for submission and it is I who was running an older version > > > of t_dir_offset2. Let me figure this out and get back to you > > > with a working test. > > > > > > > How about you try again with a version of the test that actually has > > the check and the error print that I reported.... ;-) > > > > P.S.1: > xino=on is futile for this test as it uses all layers on same fs > > P.S.2: > The attached patch to t_dir_offset2 only reproduces the first > inconsistency I reported: > entry m100 has inconsistent d_ino (234 != 232) > > The second inconsistency requires another small patch to overlay/077 > (attached). I will post both those patches once the kernel fix is in > overlayfs-next. Thanks. Verified and pushed. Miklos