Re: [PATCH v14 1/3] safemath: Add ALIGN_UP_OVF() that checks for {over,under}flow

[Gao Xiang]

Hi Daniel,

There is too many comments on this minor stuff, would you mind
giving some hints of your perference so I could have a chance
to finish this stuff?

https://lore.kernel.org/grub-devel/CAEaD8JNwa8W=3LvaVeDG0hByz10+XHEDwCsV8TQe5md_13s2jg@mail.gmail.com/
8f2512f9-e851-467c-bbb8-450bf0219696@gmail.com/">https://lore.kernel.org/grub-devel/8f2512f9-e851-467c-bbb8-450bf0219696@gmail.com/

Thanks in advance.

Thanks,
Gao Xiang

On 2024/5/19 11:21, Gao Xiang wrote:
> On 2024/5/18 17:20, Vladimir 'phcoder' Serbinenko wrote:
> > Le ven. 17 mai 2024, 21:26, Gao Xiang <hsiangkao@linux.alibaba.com 
> > <mailto:hsiangkao@linux.alibaba.com>> a écrit :
> >
> >     Hi Vladimir,
> >
> >     On 2024/5/18 00:38, Vladimir 'phcoder' Serbinenko wrote:
> >      > I think that given that align is a non zero const we can trust it.
> >
> >       From the EROFS specific cases, they are always non-zero values,
> >     So I agree with you on this..
> >
> >     Yet Daniel said ".. Be careful with underflows too." in
> >     Zkcv7G7MJBg8sKiE@tomti.i.net-space.pl">https://lore.kernel.org/r/Zkcv7G7MJBg8sKiE@tomti.i.net-space.pl 
> > <Zkcv7G7MJBg8sKiE@tomti.i.net-space.pl">https://lore.kernel.org/r/Zkcv7G7MJBg8sKiE@tomti.i.net-space.pl>
> >     although I'm not quite sure but I guess like this.
> >
> >     Also as a generic helper, I think `align` could be zero if it's
> >     a variable..
> >
> >
> > It's rare for align to be a variable and then additional checks are needed that 
> > align is a power of 2. And power of 2 is never zero. This check is better done 
> > on the caller side. You just need a comment specify that it's caller 
> > responsibility to check it.
>
> I'd like to know Daniel's comment about this first, there are already
> too many comments out of nits.  I'm fine with updating such nits but
> I would like to confirm _which comment_ I should follow for
> upstreaming.
>
> Thanks,
> Gao Xiang
>
> >     Anyway, either way works for EROFS.   I just try my best to do
> >     what I could do for this first series for upstreaming and we
> >     could move forward to the next step..
> >
> >     Thanks,
> >     Gao Xiang