From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B390A2D6E5C; Mon, 24 Aug 2026 16:45:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787589919; cv=none; b=LIFhTfp2X0s/P4zDSw4IgjkVLwzmozGiaJ39pkhqbrOXIt5tKYAxEzRrJ46pfGnUp1cPqg/k82G0giRYv5JQq4TV9T29o8/h2SH6xp41PueaSBMljao1xWMk+TyUj9idoQ1N617CQEzdLZU+QcQLCWX0w7IN0F3Q3TaHdi0ERQY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787589919; c=relaxed/simple; bh=KdRaFH418IwMoBjR352tUzLF0FQnVwNdbVBgQtfPdUc=; h=Date:From:To:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tAiJXXiZmCySSSsI9DsrHImVWPGI4LQj5TyYQWEKRC5IKGNARL8vgA+1feNgEsA20dka3ZjLSbNrWf00lcpH80M9okLzv7t2TLCao8sbq7PxGHodAMIGT20ZcaNBJug7A51CgI30RqPwwVU2TclU/plF+j3kqugfX07c1dwSy+I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UcR0S5xs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UcR0S5xs" Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id 499601F000E9; Mon, 24 Aug 2026 16:45:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787589917; bh=oAUtDi8en9QZvGlCLffFVyYo7kvY8dRwLy48GSmtj/Q=; h=Date:From:To:Subject:References:In-Reply-To; b=UcR0S5xswRIhaN/PB9yxCRfuuQrLwZWwo4dHgdbhOuHxiNgRwClbhjAM0/n/nC93X 7QOtfIb8Zf89e12YeZa7GxDNTISdRhBgVvSLFXEqR1Q0BD+eEd9v3xOWOEu/m8g72y K8DfRwgA0wqNRsz9qJcYVBvdJWiLy1C51zQJcEM37Cd6/A45N7PEyNIGIx6R4psvtB t2a3FyiYs5qjHovb0FkSr82Kxt6VgDG3Lu/k7PE8+9bOpUaVz9KM9O7KGM9XbDGVs+ FhDWQac6BKAsNX/Bndy9FGCzdRNpjRCa37bHeUIwueYIZyeoIaPqNYqJx+6sxnho8X YcEc8A2WE3iog== Date: Mon, 24 Aug 2026 09:45:16 -0700 From: "Darrick J. Wong" To: qsa@qualys.com, fstests , xfs Subject: Re: [PATCH v2] generic: regression test for refluxfs fixes Message-ID: <20260824164516.GF6110@frogsfrogsfrogs> References: <20260821235155.GK839663@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: fstests@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Aug 24, 2026 at 10:05:25PM +0800, Zorro Lang wrote: > On Fri, Aug 21, 2026 at 04:51:55PM -0700, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > Regression test for refluxfs as found by Qualys. > > > > Reported-by: qsa@qualys.com > > Co-developed-by: qsa@qualys.com > > Signed-off-by: "Darrick J. Wong" > > --- > > v2: add co-author credits > > --- > > Hi Darrick, > > I just gave this patch a try on linux v7.2+ which contains the commit > 2f4acd0fcd862e, but the test still fails as shown below on both xfs > and btrfs. Did I miss anything? > > root@bogon:~/git/linux# git tag --contains 2f4acd0fcd862e > v7.2 > v7.2-rc4 > v7.2-rc5 > v7.2-rc6 > v7.2-rc7 > > root@bogon:~/git/xfstests-dev# ./check generic/1956 > FSTYP -- xfs (debug) > PLATFORM -- Linux/x86_64 bogon 7.2.0-mainline+ #3 SMP PREEMPT_DYNAMIC Mon Aug 24 20:34:26 CST 2026 > MKFS_OPTIONS -- -f /dev/sdc1 > MOUNT_OPTIONS -- -o context=system_u:object_r:root_t:s0 /dev/sdc1 /mnt/scratch > > generic/1956 - output mismatch (see /root/git/xfstests-dev/results//generic/1956.out.bad) > --- tests/generic/1956.out 2026-08-24 14:19:18.790104900 +0800 > +++ /root/git/xfstests-dev/results//generic/1956.out.bad 2026-08-24 21:41:51.884222239 +0800 > @@ -1,2 +1,2 @@ > QA output created by 1956 > -corruption not observed > +unknown outcome 126 126 is probably su trying to communicate that it couldn't actually run refluxfs. _require_test_program should have _notrun if the binary didn't build, so ... I don't know what's going on here. Does $seqres.full have anything interesting to say? Or does su'ing to fsgqa not work? (FWIW it works fine on my system even with large block size) --D > ... > (Run 'diff -u /root/git/xfstests-dev/tests/generic/1956.out /root/git/xfstests-dev/results//generic/1956.out.bad' to see the entire diff) > > HINT: You _MAY_ be missing kernel fix: > 2f4acd0fcd862e xfs: resample the data fork mapping after cycling ILOCK > > Ran: generic/1956 > Failures: generic/1956 > Failed 1 of 1 tests > > root@bogon:~/git/xfstests-dev# ./check generic/1956 > FSTYP -- btrfs > PLATFORM -- Linux/x86_64 bogon 7.2.0-mainline+ #3 SMP PREEMPT_DYNAMIC Mon Aug 24 20:34:26 CST 2026 > MKFS_OPTIONS -- /dev/sdc1 > MOUNT_OPTIONS -- -o context=system_u:object_r:root_t:s0 /dev/sdc1 /mnt/scratch > > generic/1956 - output mismatch (see /root/git/xfstests-dev/results//generic/1956.out.bad) > --- tests/generic/1956.out 2026-08-24 14:19:18.790104900 +0800 > +++ /root/git/xfstests-dev/results//generic/1956.out.bad 2026-08-24 21:44:35.654443414 +0800 > @@ -1,2 +1,2 @@ > QA output created by 1956 > -corruption not observed > +unknown outcome 126 > ... > (Run 'diff -u /root/git/xfstests-dev/tests/generic/1956.out /root/git/xfstests-dev/results//generic/1956.out.bad' to see the entire diff) > Ran: generic/1956 > Failures: generic/1956 > Failed 1 of 1 tests > > > > .gitignore | 1 > > src/Makefile | 2 > > src/refluxfs.c | 461 ++++++++++++++++++++++++++++++++++++++++++++++++ > > tests/generic/1956 | 58 ++++++ > > tests/generic/1956.out | 2 > > 5 files changed, 523 insertions(+), 1 deletion(-) > > create mode 100644 src/refluxfs.c > > create mode 100755 tests/generic/1956 > > create mode 100644 tests/generic/1956.out > > > > [snip] > > > +#ifndef FICLONE > > +#define FICLONE _IOW(0x94, 9, int) > > +#endif > > +#ifndef XFS_SUPER_MAGIC > > +#define XFS_SUPER_MAGIC 0x58465342 > > +#endif > > + > > +#define BLK 4096 > > This's a hard code, what if the fs blocksize or pagesize isn't 4096? > > > + > > +/* ---- configuration (overridable via CLI) --------------------------------- */ > > +static const char *target_path = "/etc/passwd"; > > +static const char *clone_dir = "/var/tmp"; > > +static int nr_writers = 32; > > +static int nr_pressure = 8; > > +static int budget_s = 300; > > + > > [snip] > > > + > > +#if 0 > > +static int is_xfs(const char *p) > > +{ > > + struct statfs s; > > + if (statfs(p, &s)) return -1; > > + return s.f_type == XFS_SUPER_MAGIC; > > +} > > +#endif > > If this's useless, how about remove them? > > > + > > +/* FIEMAP: is the target's first extent already shared (refcount > 1)? > > + * If so the race can never see refcount==1. */ > > +static int target_first_extent_shared(void) > > +{ > > [snip] > > > +#if 0 > > + /* 2. target on XFS */ > > + int x = is_xfs(target_path); > > + if (x < 0) die(1, "statfs target", NULL); > > + if (!x) { > > + BAD("target is not on XFS (f_type != XFS_SUPER_MAGIC)."); > > + INFO("RefluXFS only affects XFS with reflink=1 (mkfs.xfs default since"); > > + INFO("xfsprogs 5.1.0; backported by Red Hat for RHEL 8 GA). Default root"); > > + INFO("fs on RHEL/CentOS/Rocky/Alma/OL/CloudLinux 8+, Fedora Server 31+,"); > > + INFO("Amazon Linux 2023."); > > + exit(1); > > + } > > + OK("target is on XFS"); > > +#endif > > Same > > > + > > + /* 3. clone_dir on the same superblock */ > > + if (access(clone_dir, W_OK)) die(1, "clone dir not writable", > > + "Need a writable directory on the SAME XFS filesystem as the target."); > > [snip] > > > +static void *pressure(void *arg) > > +{ > > + char p[600]; > > + snprintf(p, sizeof p, "%s/press.%d", workdir, (int)(intptr_t)arg); > > + int fd = open(p, O_RDWR|O_CREAT|O_TRUNC, 0600); > > + if (fd < 0) return NULL; > > + char b = 0; > > + while (!atomic_load(&stop)) { > > + /* return values irrelevant -- goal is XFS log traffic, not the data */ > > + (void)!pwrite(fd, &b, 1, 0); > > + (void)!ftruncate(fd, BLK); > > + fdatasync(fd); > > + (void)!ftruncate(fd, 0); > > As this's a generic test case, the pressure() works for XFS CIL, does it work > for other filesystems? > > Thanks, > Zorro