Re: [PATCH] fstests: support new mkfs.btrfs help string

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

在 2026/5/11 04:39, Zorro Lang 写道:
> On Sun, May 10, 2026 at 09:47:04AM +0930, Qu Wenruo wrote:
>> [BUG]
>> The latest btrfs-progs release v7.0 breaks a lot of tests, e.g.
>> btrfs/003:
>>
>> btrfs/003    55s ... [failed, exit status 1]- output mismatch (see /home/kts/kernel-test-suite/src/xfstests/results//btrfs/003.out.bad)
>>      --- tests/btrfs/003.out     2026-05-09 03:07:52.952213772 +0900
>>      +++ /home/kts/kernel-test-suite/src/xfstests/results//btrfs/003.out.bad     2026-05-09 23:32:17.595751435 +0900
>>      @@ -1,2 +1,3 @@
>>       QA output created by 003
>>      -Silence is golden
>>      +mkfs failed
>>      +(see /home/kts/kernel-test-suite/src/xfstests/results//btrfs/003.full for details)
>>      ...
>>      (Run 'diff -u /home/kts/kernel-test-suite/src/xfstests/tests/btrfs/003.out /home/kts/kernel-test-suite/src/xfstests/results//btrfs/003.out.bad'  to see the entire diff)
>>
>> [CAUSE]
>> Commit ec8324cc4b8b ("btrfs-progs: help: adjust alignment of text") from
>> btrfs-progs changed the helpe string output format, the previous help
>> string for "-f" option of mkfs.btrfs looks like this:
>>
>>      -f|--force                force overwrite of existing filesystem
>>
>> There were 4 spaces before the "-f", thus can be matched by
>> "[[:space:]]-f[[:space]|,]".
>>
>> But now the help string looks like:
>>
>> -f, --force               force overwrite of existing filesystem
>>
>> Which removed the spaces at the beginning.
>>
>> The existing regex to catch "-f" requires at least one space before
>> "-f", now it doesn't match the new btrfs help string, and cause mkfs
>> failure because we can not overwrite an existing scratch device without
>> "-f" option.
>>
>> [FIX]
>> Change the regex to allow no space before "-f".
>>
>> Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
>> Link: https://lore.kernel.org/linux-btrfs/af9EHC5b-aBdr1zn@shinmob/
>> Signed-off-by: Qu Wenruo <wqu@suse.com>
>> ---
>>   common/config | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/common/config b/common/config
>> index 1420e35d..339f7767 100644
>> --- a/common/config
>> +++ b/common/config
>> @@ -103,7 +103,7 @@ set_mkfs_prog_path_with_opts()
>>   	# Note: mkfs.f2fs doesn't support the --help option yet, but it doesn't
>>   	# matter since it also prints the help when an invalid option is given.
>>   	if [ "$p" != "" ] && \
>> -		$p --help |& grep -q "[[:space:]]-f[[:space:]|,]"; then
>> +		$p --help |& grep -q "[[:space:]]*-f[[:space:]|,]"; then
> 
> Hi Qu,
> 
> This change looks good to me. But to be a bit nitpicky, the original
> "[[:space:]]-f" required *a* mandatory [space] before the -f, whereas
> "[[:space:]]*-f" allows for *zero* or more spaces. This changes the
> semantics slightly, but it makes sense if you're trying to match cases
> where -f appears at the very beginning of a line.

That's exactly my intention.
Also explained in the commit message:

    The existing regex to catch "-f" requires at least one space before
    "-f", now it doesn't match the new btrfs help string,

And

    Change the regex to allow no space before "-f".

Thanks,
Qu

> 
> If that wasn't your intention or if you find this behavior unexpected, let me
> know :) Otherwise, I'd like to:
> 
> Reviewed-by: Zorro Lang <zlang@kernel.org>
> 
>>   		echo "$p -f"
>>   	else
>>   		echo $p
>> -- 
>> 2.51.2
>>
>>
>