Subject: Re: [PATCH 0/4] net: drop netif_attrmask_next*()

From: Jakub Kicinski <[email-masked]>
Date: Mon, 3 Oct 2022 16:25:56 -0700

On Mon, 3 Oct 2022 11:11:05 -0700 Yury Norov wrote:
> On Mon, Oct 03, 2022 at 09:50:48AM -0700, Jakub Kicinski wrote:
> > On Sun,  2 Oct 2022 08:16:58 -0700 Yury Norov wrote:  
> > > netif_attrmask_next_and() generates warnings if CONFIG_DEBUG_PER_CPU_MAPS
> > > is enabled.  
> > 
> > Could you describe the nature of the warning? Is it a false positive 
> > or a legit warning?
> > 
> > If the former perhaps we should defer until after the next merge window.  
> 
> The problem is that netif_attrmask_next_and() is called with
> n == nr_cpu_ids-1, which triggers cpu_max_bits_warn() after this:
> 
> https://lore.kernel.org/netdev/[email-masked]/

I see. Is that patch merged and on it's way? Perhaps we can just revert
it and try again after the merge window?

> Underlying bitmap layer handles this correctly, so this wouldn't make
> problems for people. But this is not a false-positive.