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Date: Mon, 9 Jun 2025 15:57:29 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Denis Arefev <arefev@swemel.ru>
Cc: "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Simon Horman
 <horms@kernel.org>, Nikita Marushkin <hfggklm@gmail.com>, Ilya Shchipletsov
 <rabbelkin@mail.ru>, Hongbo Li <lihongbo22@huawei.com>,
 linux-hams@vger.kernel.org, netdev@vger.kernel.org,
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 stable@vger.kernel.org,
 syzbot+ccdfb85a561b973219c7@syzkaller.appspotmail.com
Subject: Re: [PATCH net] netrom: fix possible deadlock in nr_rt_device_down
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On Thu,  5 Jun 2025 13:54:48 +0300 Denis Arefev wrote:
> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

I suspect syzbot is the only user of this code.
Can you delete one of the locks to make the maintenance simpler?
At a glance - I don't think your fix covers all the ABBA cases.
-- 
pw-bot: cr