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Date:   Wed, 9 Nov 2022 13:45:36 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Eric Dumazet <edumazet@google.com>
Cc:     Ido Schimmel <idosch@idosch.org>, Jiri Pirko <jiri@resnulli.us>,
        netdev@vger.kernel.org, davem@davemloft.net, pabeni@redhat.com,
        bigeasy@linutronix.de, imagedong@tencent.com, kuniyu@amazon.com,
        petrm@nvidia.com
Subject: Re: [patch net-next v2 3/3] net: devlink: add WARN_ON to check
 return value of unregister_netdevice_notifier_net() call
Message-ID: <20221109134536.447890fb@kernel.org>
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On Wed, 9 Nov 2022 08:26:10 -0800 Eric Dumazet wrote:
> > On Tue, Nov 08, 2022 at 02:22:08PM +0100, Jiri Pirko wrote:  
> > > From: Jiri Pirko <jiri@nvidia.com>
> > >
> > > As the return value is not 0 only in case there is no such notifier
> > > block registered, add a WARN_ON() to yell about it.
> > >
> > > Suggested-by: Ido Schimmel <idosch@idosch.org>
> > > Signed-off-by: Jiri Pirko <jiri@nvidia.com>  
> >
> > Reviewed-by: Ido Schimmel <idosch@nvidia.com>  
> 
> Please consider WARN_ON_ONCE(), or DEBUG_NET_WARN_ON_ONCE()

Do you have any general guidance on when to pick WARN() vs WARN_ONCE()?
Or should we always prefer _ONCE() going forward?

Let me take the first 2 in, to lower the syzbot volume.