Re: [PATCH v2] fstests: btrfs/315: fix golden output mismatch caused by newer util-linux

[Anand Jain <anand.jain@oracle.com>]

On 24/4/25 12:59, Qu Wenruo wrote:
> [BUG]
> With util-linux v2.41.0 and newer, test case btrfs/315 will fail like
> the following:
> 
> btrfs/315 1s ... - output mismatch (see /home/adam/xfstests-dev/results//btrfs/315.out.bad)
>      --- tests/btrfs/315.out	2025-04-24 15:31:28.684112371 +0930
>      +++ /home/adam/xfstests-dev/results//btrfs/315.out.bad	2025-04-24 15:31:31.854883557 +0930
>      @@ -1,7 +1,7 @@
>       QA output created by 315
>       ---- seed_device_must_fail ----
>       mount: SCRATCH_MNT: WARNING: source write-protected, mounted read-only.
>      -mount: TEST_DIR/315/tempfsid_mnt:  system call failed: File exists.
>      +mount: TEST_DIR/315/tempfsid_mnt: () failed: File exists.
>       ---- device_add_must_fail ----
>       wrote 9000/9000 bytes at offset 0
> 
> [CAUSE]
> 
> With util-linux v2.41.0, the mount failure error message changed to the following:
> 
>    mount: /mnt/test/315/tempfsid_mnt: fsconfig() failed: File exists.
> 
> Thus the existing filter only striped the "fsconfig" part, leaving the
> "()" without changing it to " system call".
> 
> [FIX]
> The test case is doomed in day one by using a local filter, which
> requires stupid catch-up game against util-linux.
> 
> Meanwhile we already have a much better filter, _filter_error_mount().
> That helper can already handle the newer v2.41 output.
> 
> Let's use the superior common filter and update the golden output to:
> 
>    mount: File exists.
> 
> Signed-off-by: Qu Wenruo <wqu@suse.com>
> ---
> Changelog:
> v2:
> - Remove the cursed local filter and use the generic one instead
> ---
>   tests/btrfs/315     | 22 ++--------------------
>   tests/btrfs/315.out |  2 +-
>   2 files changed, 3 insertions(+), 21 deletions(-)
> 
> diff --git a/tests/btrfs/315 b/tests/btrfs/315
> index e6589abe..9071e152 100755
> --- a/tests/btrfs/315
> +++ b/tests/btrfs/315
> @@ -19,6 +19,7 @@ _cleanup()
>   }
>   

>   . ./common/filter.btrfs
> +. ./common/filter

common/filter.btrfs calls common/filter, so we don't need common/filter
again. However, upon closer inspection, there isn't a filter originating
from filter.btrfs, so it can be removed.

Fixed and applied.

Reviewed-by: Anand Jain <anand.jain@oracle.com>

Thanks. Anand

>   _require_scratch_dev_pool 3
>   _require_btrfs_fs_feature temp_fsid
> @@ -28,25 +29,6 @@ _scratch_dev_pool_get 3
>   # mount point for the tempfsid device
>   tempfsid_mnt=$TEST_DIR/$seq/tempfsid_mnt
>   
> -_filter_mount_error()
> -{
> -	# There are two different errors that occur at the output when
> -	# mounting fails; as shown below, pick out the common part. And,
> -	# remove the dmesg line.
> -
> -	# mount: <mnt-point>: mount(2) system call failed: File exists.
> -
> -	# mount: <mnt-point>: fsconfig system call failed: File exists.
> -	# dmesg(1) may have more information after failed mount system call.
> -
> -	# For util-linux v2.4 and later:
> -	# mount: <mountpoint>: mount system call failed: File exists.
> -
> -	grep -v dmesg | _filter_test_dir | \
> -		sed -e "s/mount(2)\|fsconfig//g" \
> -		    -e "s/mount\( system call failed:\)/\1/"
> -}
> -
>   seed_device_must_fail()
>   {
>   	echo ---- $FUNCNAME ----
> @@ -57,7 +39,7 @@ seed_device_must_fail()
>   	$BTRFS_TUNE_PROG -S 1 ${SCRATCH_DEV_NAME[1]}
>   
>   	_scratch_mount 2>&1 | _filter_scratch
> -	_mount ${SCRATCH_DEV_NAME[1]} ${tempfsid_mnt} 2>&1 | _filter_mount_error
> +	_mount ${SCRATCH_DEV_NAME[1]} ${tempfsid_mnt} 2>&1 | _filter_error_mount
>   }
>   
>   device_add_must_fail()
> diff --git a/tests/btrfs/315.out b/tests/btrfs/315.out
> index 3ea7a35a..ae77d4fd 100644
> --- a/tests/btrfs/315.out
> +++ b/tests/btrfs/315.out
> @@ -1,7 +1,7 @@
>   QA output created by 315
>   ---- seed_device_must_fail ----
>   mount: SCRATCH_MNT: WARNING: source write-protected, mounted read-only.
> -mount: TEST_DIR/315/tempfsid_mnt:  system call failed: File exists.
> +mount: File exists
>   ---- device_add_must_fail ----
>   wrote 9000/9000 bytes at offset 0
>   XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)