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Date: Sun, 1 Mar 2026 11:36:43 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Eric Dumazet <edumazet@google.com>
Cc: "David S . Miller" <davem@davemloft.net>, Paolo Abeni
 <pabeni@redhat.com>, Simon Horman <horms@kernel.org>, David Ahern
 <dsahern@kernel.org>, Kuniyuki Iwashima <kuniyu@google.com>,
 netdev@vger.kernel.org, eric.dumazet@gmail.com, Ido Schimmel
 <idosch@nvidia.com>
Subject: Re: [PATCH net-next] ipv6: add IPV6_CALL() helper
Message-ID: <20260301113643.65e4e90c@kernel.org>
In-Reply-To: <20260301112413.1b6c785e@kernel.org>
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	<20260301112413.1b6c785e@kernel.org>
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On Sun, 1 Mar 2026 11:24:13 -0800 Jakub Kicinski wrote:
> On Sun,  1 Mar 2026 16:25:14 +0000 Eric Dumazet wrote:
> > ipv6_stub use is racy, we should add READ_ONCE() and WRITE_ONCE(),
> > even if this pointer can only change once.
> > 
> > Add IPV6_CALL() macro to factorize the READ_ONCE(), and perform
> > direct calls when CONFIG_IPV6=y.  
> 
> Some crashiness detected here, I think

Took me a minute to grok it but its obvious in hindsight so to possibly
save you time: fib6_update_sernum_stub() vs fib6_update_sernum()
We now call the wrong function due to the funny naming.