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Date: Mon, 18 Dec 2023 12:19:08 +0100
From: Steffen Klassert <steffen.klassert@secunet.com>
To: Eric Dumazet <edumazet@google.com>
CC: Zhang Yiqun <zhangyiqun@phytium.com.cn>, <herbert@gondor.apana.org.au>,
	<davem@davemloft.net>, <kuba@kernel.org>, <pabeni@redhat.com>,
	<netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] xfrm: Use spin_lock_bh() in xfrm_input()
Message-ID: <ZYAqrDSp6QuKv5I0@gauss3.secunet.de>
References: <20231218084252.7644-1-zhangyiqun@phytium.com.cn>
 <CANn89i+t9t5ca=r6ZKw7s-HrxzgJjCB6hmWLccKmmxg8H=HUUA@mail.gmail.com>
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On Mon, Dec 18, 2023 at 12:07:50PM +0100, Eric Dumazet wrote:
> On Mon, Dec 18, 2023 at 9:43 AM Zhang Yiqun <zhangyiqun@phytium.com.cn> wrote:
> >
> > This patch is to change spin_lock() into spin_lock_bh(), which can
> > disable bottem half in calling. If we leave this as spin_lock(),
> > it may stuck in a deadlock, because the callback in bottem half in
> > crypto driver will also call xfrm_input() again.
> >
> > Signed-off-by: Zhang Yiqun <zhangyiqun@phytium.com.cn>
> 
> When was the bug added ?
> We need a FIxes: tag.

This looks more like a 'crypto driver' bug. xfrm_input() runs in
the RX path and therefore expects to run with BHs off.