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Date: Tue, 4 Feb 2025 13:00:25 -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>, netdev@vger.kernel.org, Kuniyuki Iwashima
 <kuniyu@amazon.com>, Simon Horman <horms@kernel.org>,
 eric.dumazet@gmail.com, rcu@vger.kernel.org
Subject: Re: [PATCH v3 net 11/16] ipv6: input: convert to dev_net_rcu()
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On Tue, 4 Feb 2025 21:10:59 +0100 Eric Dumazet wrote:
> > Test output:
> > https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/978202/61-l2tp-sh/
> > Decoded:
> > https://netdev-3.bots.linux.dev/vmksft-net-dbg/results/978202/vm-crash-thr2-0  
> 
> Oh well. So many bugs.

TBH I'm slightly confused by this, and the previous warnings.

The previous one was from a timer callback.

This one is with BH disabled.

I thought BH implies RCU protection. We certainly depend on that 
in NAPI for XDP. And threaded NAPI does the exact same thing as
xfrm_trans_reinject(), a bare local_bh_disable().

RCU folks, did something change or is just holes in my brain again?