From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <xiyou.wangcong@gmail.com>
Subject: Re: [Patch net] net: saving irq context for peernet2id()
Date: Thu, 20 Oct 2016 10:17:23 -0700
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Stephen Smalley <sds@tycho.nsa.gov>, Elad Raz <e@eladraz.com>,
        Paul Moore <paul@paul-moore.com>
To: Nicolas Dichtel <nicolas.dichtel@6wind.com>
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On Thu, Oct 20, 2016 at 3:17 AM, Nicolas Dichtel
<nicolas.dichtel@6wind.com> wrote:
>
> Now, we see that "it's needed" and that the analysis was wrong. If a race is
> introduced by this patch, it will be hard to detect and fix it.

It is _not_ needed for protection, it is needed to shut up a warning, I thought
this is pretty clear in the changelog.

If we could invent some way to save BH (*lock_bhsave()), we don't need
to bother this at all, currently we don't.