Re: [PATCH] quotactl.2: Remove kernel version for Q_XQUOTARM ioctl

["xuyang2018.jy@fujitsu.com" <xuyang2018.jy@fujitsu.com>]

on 2021/11/5 4:10, Alejandro Colomar (man-pages) wrote:
> Hi Jan and Yang,
>
> On 11/4/21 11:53, Jan Kara wrote:
>> On Thu 04-11-21 00:58:02, xuyang2018.jy@fujitsu.com wrote:
>>>>>>>> This patch[1] is designed to fix bug for Q_XQUOTARM ioctl not for
>>>>>>>> introduced.
>>>>>>>> So remove it.
>>>>>>>>
>>>>>>>> [1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9da93f9b7c
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Signed-off-by: Yang Xu<xuyang2018.jy@fujitsu.com>
>>>>>>>> ---
>>>>>>>> man2/quotactl.2 | 3 +--
>>>>>>>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>>>>>>>
>>>>>>>> diff --git a/man2/quotactl.2 b/man2/quotactl.2
>>>>>>>> index d22d8c584..46f77a8b1 100644
>>>>>>>> --- a/man2/quotactl.2
>>>>>>>> +++ b/man2/quotactl.2
>>>>>>>> @@ -651,8 +651,7 @@ The
>>>>>>>> .I id
>>>>>>>> argument is ignored.
>>>>>>>> .TP
>>>>>>>> -.B Q_XQUOTARM " (since Linux 3.16)"
>>>>>>>> -.\" 9da93f9b7cdf8ab28da6b364cdc1fafc8670b4dc
>
> I applied the patch.

Thanks.

>>>>
>>>> Okay. Since you added that line (man-pages commit ae848b1d80), I'm fine
>>>> removing it. Was it a mistake? The commit message of that commit is a
>>>> bit unrelated to Q_XQUOTARM, isn't it?
>>> Yes.
>>
>> Well, that commit fixed Q_XQUOTARM quotactl. Previously it was supported
>> but it was buggy and not actually doing the desired functionality in some
>> cases. So the description kind of make sense but it is not quite
>> accurate -
>> maybe we should just move the note to NOTES section?
>
> I think we better add a BUGS section. Don't you?
> Unless you think it isn't important enough. How likely is it that
> Q_XQUOTARM was used in kernels before 3.16 and a BUGS section will help
> fix the bug? And how likely is it that someone will use it in the future
> for kernels before 3.16? How important/dangerous was the bug?
@Jan
I doubt this ioctl whether be used by any application.

ps:I also increase ltp quotactl coverage to cover quotactl_fd syscall. I 
would appreciate it if you could review my ltp quotactl/quotactl_fd patchset
https://patchwork.ozlabs.org/project/ltp/list/?series=269166


>
> Maybe add something simpler such as "(buggy until Linux 3.16)" so that
> no one uses it in older kernels but doesn't use as much space as a new
> BUGS section?
@Alejandro
If this ioctl doesn't be used by many application(IMO,it is rare to be 
used ),  using "(buggy until Linux 3.16)" is better.

Best Regards
Yang Xu
>
>>
>>>> Maybe a better fix would be to replace the kernel version and the
>>>> commit
>>>> hash when it was really added?
>>> Yes, but I can't find this commit hash and it seems been supported since
>>> long time ago.
>>
>> Yeah, AFAIK Q_XQUOTARM is there in principle since XFS was introduced in
>> the linux kernel so around 2001. No point of mentioning that in the
>> manpage
>> IMO.
>>
>> Honza
>>
>
> Thanks,
>
> Alex
>
>