[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAJF2gTQyMHNHLizeU-gvUdA5hRLUWxvHXuVVqSoPg3M_WxPPdw@mail.gmail.com>
Date: Fri, 14 Oct 2022 14:38:56 +0800
From: Guo Ren <guoren@...nel.org>
To: Jakub Kicinski <kuba@...nel.org>
Cc: andriy.shevchenko@...ux.intel.com, davem@...emloft.net,
edumazet@...gle.com, pabeni@...hat.com, linux@...musvillemoes.dk,
yury.norov@...il.com, caraitto@...gle.com, willemb@...gle.com,
jonolson@...gle.com, amritha.nambiar@...el.com,
linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
Guo Ren <guoren@...ux.alibaba.com>
Subject: Re: [PATCH V2 1/2] net: Fixup netif_attrmask_next_and warning
On Fri, Oct 14, 2022 at 11:35 AM Jakub Kicinski <kuba@...nel.org> wrote:
>
> On Thu, 13 Oct 2022 23:04:58 -0400 guoren@...nel.org wrote:
> > - for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
> > - j < nr_ids;) {
> > + for (j = -1; j < nr_ids;
> > + j = netif_attrmask_next_and(j, online_mask, mask, nr_ids)) {
>
> This does not look equivalent, have you tested it?
>
> nr_ids is unsigned, doesn't it mean we'll never enter the loop?
Yes, you are right. Any unsigned int would break the result.
(gdb) p (int)-1 < (int)2
$1 = 1
(gdb) p (int)-1 < (unsigned int)2
$2 = 0
(gdb) p (unsigned int)-1 < (int)2
$4 = 0
So it should be:
- for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
- j < nr_ids;) {
+ for (j = -1; j < (int)nr_ids;
+ j = netif_attrmask_next_and(j, online_mask, mask, nr_ids)) {
Right? Of cause, nr_ids couldn't be 0xffffffff (-1).
>
> Can we instead revert 854701ba4c and take the larger rework Yury
> has posted a week ago into net-next?
--
Best Regards
Guo Ren
Powered by blists - more mailing lists