From: Filipe Manana <fdmanana@kernel.org>
To: Josef Bacik <josef@toxicpanda.com>
Cc: linux-btrfs@vger.kernel.org, fstests@vger.kernel.org, kernel-team@fb.com
Subject: Re: [PATCH] fstests: add a regression test for fiemap into an mmap range
Date: Fri, 2 Feb 2024 11:42:46 +0000 [thread overview]
Message-ID: <CAL3q7H4JsWsW2Ng2DzZj6zwg+qio86w48T9qCd7VXXfkv4nGMg@mail.gmail.com> (raw)
In-Reply-To: <795fcb629a2bbfeaf39023d971b7cb3a468aa87f.1706819794.git.josef@toxicpanda.com>
On Thu, Feb 1, 2024 at 8:37 PM Josef Bacik <josef@toxicpanda.com> wrote:
>
> Btrfs had a deadlock that you could trigger by mmap'ing a large file and
> using that as the buffer for fiemap. This test adds a c program to do
> this, and the fstest creates a large enough file and then runs the
> reproducer on the file. Without the fix btrfs deadlocks, with the fix
> we pass fine.
>
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> ---
> src/Makefile | 2 +-
> tests/generic/740 | 41 +++++++++++++++++++++++++++++++++++++++++
> tests/generic/740.out | 2 ++
> 3 files changed, 44 insertions(+), 1 deletion(-)
> create mode 100644 tests/generic/740
> create mode 100644 tests/generic/740.out
>
> diff --git a/src/Makefile b/src/Makefile
> index d79015ce..916f6755 100644
> --- a/src/Makefile
> +++ b/src/Makefile
> @@ -34,7 +34,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
> attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \
> fscrypt-crypt-util bulkstat_null_ocount splice-test chprojid_fail \
> detached_mounts_propagation ext4_resize t_readdir_3 splice2pipe \
> - uuid_ioctl
> + uuid_ioctl fiemap-fault
>
> EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \
> btrfs_crc32c_forged_name.py popdir.pl popattr.py \
> diff --git a/tests/generic/740 b/tests/generic/740
> new file mode 100644
> index 00000000..46ec5820
> --- /dev/null
> +++ b/tests/generic/740
> @@ -0,0 +1,41 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2023 Meta Platforms, Inc. All Rights Reserved.
> +#
> +# FS QA Test 708
> +#
> +# Test fiemap into an mmaped buffer of the same file
> +#
> +# Create a reasonably large file, then run a program which mmaps it and uses
> +# that as a buffer for an fiemap call. This is a regression test for btrfs
> +# where we used to hold a lock for the duration of the fiemap call which would
> +# result in a deadlock if we page faulted.
> +#
> +. ./common/preamble
> +_begin_fstest quick auto
Besides the missing C file, please also add the "fiemap" group to the test.
Thanks.
> +[ $FSTYP == "btrfs" ] && \
> + _fixed_by_kernel_commit xxxxxxxxxxxx \
> + "btrfs: fix deadlock with fiemap and extent locking"
> +
> +# real QA test starts here
> +_supported_fs generic
> +_require_test
> +_require_odirect
> +_require_test_program fiemap-fault
> +dst=$TEST_DIR/fiemap-fault-$seq
> +
> +echo "Silence is golden"
> +
> +for i in $(seq 0 2 1000)
> +do
> + $XFS_IO_PROG -d -f -c "pwrite -q $((i * 4096)) 4096" $dst
> +done
> +
> +$here/src/fiemap-fault $dst > /dev/null || _fail "failed doing fiemap"
> +
> +rm -f $dst
> +
> +# success, all done
> +status=$?
> +exit
> +
> diff --git a/tests/generic/740.out b/tests/generic/740.out
> new file mode 100644
> index 00000000..3f841e60
> --- /dev/null
> +++ b/tests/generic/740.out
> @@ -0,0 +1,2 @@
> +QA output created by 740
> +Silence is golden
> --
> 2.43.0
>
>
prev parent reply other threads:[~2024-02-02 11:43 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-01 20:36 [PATCH] fstests: add a regression test for fiemap into an mmap range Josef Bacik
2024-02-01 23:37 ` Qu Wenruo
2024-02-02 11:42 ` Filipe Manana [this message]
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