Re: [dpdk-dev] [PATCH] usertools: check 0-division with hugepage size

[Thomas Monjalon <thomas@monjalon.net>]

12/02/2021 12:27, Burakov, Anatoly:
> On 11-Feb-21 10:05 PM, Thomas Monjalon wrote:
> > The default page size can be None, and the page size from user request
> > can be 0 kB if lower than 1024. In these cases, a division will fail.
> > In order to avoid a Python exception, the page size is checked
> > and an error message "Invalid page size" is printed.
> > 
> > A similar error message is printed in set_hugepages()
> > if the size is not supported, except at this stage the message can be
> > completed with "Valid page sizes".
> > Unfortunately the first check is too early to print such information.
> > 
> > A third error message can be printed in a different place (get_memsize)
> > in case of a format issue, e.g. a negative size.
> > The function get_memsize() is also used for total requested size,
> > so the error message "not a valid page size" was potentially wrong.
> > This message is replaced with the more general "is not a valid size".
> > 
> > Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> > ---
> > @@ -254,6 +254,8 @@ def main():
> >           pagesize_kb = get_memsize(args.pagesize)
> >       else:
> >           pagesize_kb = default_pagesize()
> > +    if pagesize_kb is None or pagesize_kb == 0:
> > +        sys.exit("Invalid page size: {}kB".format(pagesize_kb))
> 
> Both None and 0 evaluate to False for boolean comparisons, so you can 
> replace it with:
> 
> if not pagesize_kb:
>     sys.exit(...)

Oh yes better :)