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Date: Wed, 23 Jul 2025 08:24:07 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Stanislav Fomichev <stfomichev@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>, netdev@vger.kernel.org,
 davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
 dsahern@kernel.org, andrew+netdev@lunn.ch, horms@kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH net 2/2] net: Warn when overriding referenced dst entry
Message-ID: <20250723082407.06686876@kernel.org>
In-Reply-To: <aID8FaYlyuVjeOH_@mini-arch>
References: <20250722210256.143208-1-sdf@fomichev.me>
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On Wed, 23 Jul 2025 08:13:25 -0700 Stanislav Fomichev wrote:
> > > +{
> > > +	DEBUG_NET_WARN_ON_ONCE(skb_dst(skb) &&
> > > +			       !(skb->_skb_refdst & SKB_DST_NOREF));  
> > 
> > Why not 
> > 
> > 	DEBUG_NET_WARN_ON_ONCE(skb->_skb_refdst & SKB_DST_PTRMASK);
> > 
> > ?  
> 
> That's more precise, agreed!

Just to be clear -- looks like I ate the

  !(skb->_skb_refdst & SKB_DST_NOREF)

part part of the condition. I think we still want that.