Re: [PATCH 12/14] xfs: test xfs_healer wont repair the wrong filesystem

Zorro Lang
2026-03-13T19:53:52Z

On Mon, Mar 09, 2026 at 08:53:15PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
>
> Make sure that when xfs_healer needs to reopen a filesystem to repair it, it
> won't latch on to another xfs filesystem that has been mounted atop the same
> mountpoint.
>
> Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
> ---

Tests and looks good to me,

Reviewed-by: Zorro Lang <zlang@redhat.com>

> tests/xfs/1901 | 137 ++++++++++++++++++++++++++++++++++++++++++++++++++++
> tests/xfs/1901.out | 2 +
> 2 files changed, 139 insertions(+)
> create mode 100755 tests/xfs/1901
> create mode 100755 tests/xfs/1901.out
>
>
> diff --git a/tests/xfs/1901 b/tests/xfs/1901
> new file mode 100755
> index 00000000000000..c92dcf9a3b3d48
> --- /dev/null
> +++ b/tests/xfs/1901
> @@ -0,0 +1,137 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2025-2026 Oracle. All Rights Reserved.
> +#
> +# FS QA Test 1901
> +#
> +# Ensure that autonomous self healing won't fix the wrong filesystem if a
> +# snapshot of the original filesystem is now mounted on the same directory as
> +# the original.
> +#
> +. ./common/preamble
> +_begin_fstest auto selfhealing
> +
> +. ./common/filter
> +. ./common/fuzzy
> +. ./common/systemd
> +
> +_cleanup()
> +{
> + command -v _kill_fsstress &>/dev/null && _kill_fsstress
> + cd /
> + rm -r -f $tmp.*
> + test -e "$mntpt" && _unmount "$mntpt" &>/dev/null
> + test -e "$mntpt" && _unmount "$mntpt" &>/dev/null
> + test -e "$loop1" && _destroy_loop_device "$loop1"
> + test -e "$loop2" && _destroy_loop_device "$loop2"
> + test -e "$testdir" && rm -r -f "$testdir"
> +}
> +
> +_require_test
> +_require_scrub
> +_require_xfs_io_command "repair" # online repair support
> +_require_xfs_db_command "blocktrash"
> +_require_command "$XFS_HEALER_PROG" "xfs_healer"
> +_require_command "$XFS_PROPERTY_PROG" "xfs_property"
> +
> +testdir=$TEST_DIR/$seq
> +mntpt=$testdir/mount
> +disk1=$testdir/disk1
> +disk2=$testdir/disk2
> +
> +mkdir -p "$mntpt"
> +$XFS_IO_PROG -f -c "truncate 300m" $disk1
> +$XFS_IO_PROG -f -c "truncate 300m" $disk2
> +loop1="$(_create_loop_device "$disk1")"
> +
> +filter_mntpt() {
> + sed -e "s|$mntpt|MNTPT|g"
> +}
> +
> +_mkfs_dev "$loop1" >> $seqres.full
> +_mount "$loop1" "$mntpt" || _notrun "cannot mount victim filesystem"
> +
> +_xfs_has_feature $mntpt rmapbt || \
> + _notrun "reverse mapping required to test directory auto-repair"
> +_xfs_has_feature $mntpt parent || \
> + _notrun "parent pointers required to test directory auto-repair"
> +_require_xfs_healer $mntpt --repair
> +
> +# Configure the filesystem for automatic repair of the filesystem.
> +$XFS_PROPERTY_PROG $mntpt set autofsck=repair >> $seqres.full
> +
> +# Create a largeish directory
> +dblksz=$(_xfs_get_dir_blocksize "$mntpt")
> +echo testdata > $mntpt/a
> +mkdir -p "$mntpt/some/victimdir"
> +for ((i = 0; i < (dblksz / 255); i++)); do
> + fname="$(printf "%0255d" "$i")"
> + ln $mntpt/a $mntpt/some/victimdir/$fname
> +done
> +
> +# Did we get at least two dir blocks?
> +dirsize=$(stat -c '%s' $mntpt/some/victimdir)
> +test "$dirsize" -gt "$dblksz" || echo "failed to create two-block directory"
> +
> +# Clone the fs, break the directory, remount filesystem
> +_unmount "$mntpt"
> +
> +cp --sparse=always "$disk1" "$disk2" || _fail "cannot copy disk1"
> +loop2="$(_create_loop_device_like_bdev "$disk2" "$loop1")"
> +
> +$XFS_DB_PROG "$loop1" -x \
> + -c 'path /some/victimdir' \
> + -c 'bmap' \
> + -c 'dblock 1' \
> + -c 'blocktrash -z -0 -o 0 -x 2048 -y 2048 -n 2048' >> $seqres.full
> +_mount "$loop1" "$mntpt" || _fail "cannot mount broken fs"
> +
> +_invoke_xfs_healer "$mntpt" "$tmp.healer" --repair
> +
> +# Stop the healer process so that it can't read error events while we do some
> +# shenanigans.
> +test -n "$XFS_HEALER_PID" || _fail "nobody set XFS_HEALER_PID?"
> +kill -STOP $XFS_HEALER_PID
> +
> +
> +echo "LOG $XFS_HEALER_PID SO FAR:" >> $seqres.full
> +cat $tmp.healer >> $seqres.full
> +
> +# Access the broken directory to trigger a repair event, which will not yet be
> +# processed.
> +ls $mntpt/some/victimdir > /dev/null 2> $tmp.err
> +filter_mntpt < $tmp.err
> +
> +ps auxfww | grep xfs_healer >> $seqres.full
> +
> +echo "LOG AFTER TRYING TO POKE:" >> $seqres.full
> +cat $tmp.healer >> $seqres.full
> +
> +# Mount the clone filesystem to the same mountpoint so that the healer cannot
> +# actually reopen it to perform repairs.
> +_mount "$loop2" "$mntpt" -o nouuid || _fail "cannot mount decoy fs"
> +
> +grep -w xfs /proc/mounts >> $seqres.full
> +
> +# Continue the healer process so it can handle events now. Wait a few seconds
> +# while it fails to reopen disk1's mount point to repair things.
> +kill -CONT $XFS_HEALER_PID
> +sleep 2
> +
> +new_dir_unmount() {
> + _unmount "$mntpt"
> + _unmount "$mntpt"
> +}
> +
> +# Unmount to kill the healer
> +_kill_xfs_healer new_dir_unmount
> +echo "LOG AFTER FAILURE" >> $seqres.full
> +cat $tmp.healer >> $seqres.full
> +
> +# Did the healer log complaints about not being able to reopen the mountpoint
> +# to enact repairs?
> +grep -q 'Stale file handle' $tmp.healer || \
> + echo "Should have seen stale file handle complaints"
> +
> +status=0
> +exit
> diff --git a/tests/xfs/1901.out b/tests/xfs/1901.out
> new file mode 100755
> index 00000000000000..ff83e03725307a
> --- /dev/null
> +++ b/tests/xfs/1901.out
> @@ -0,0 +1,2 @@
> +QA output created by 1901
> +ls: reading directory 'MNTPT/some/victimdir': Structure needs cleaning
>