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

12/02/2021 12:27, Burakov, Anatoly:

On 11-Feb-21 10:05 PM, Thomas Monjalon wrote:

quoted

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 <redacted>
---

@@ -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 :)