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Date:   Wed, 29 Jun 2022 09:17:50 -0700
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,
        eric.dumazet@gmail.com, syzbot <syzkaller@googlegroups.com>,
        Petar Penkov <ppenkov@aviatrix.com>
Subject: Re: [PATCH net] net: tun: do not call napi_disable() twice
Message-ID: <20220629091750.1f0dc8ed@kernel.org>
In-Reply-To: <20220629093752.1935215-1-edumazet@google.com>
References: <20220629093752.1935215-1-edumazet@google.com>
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On Wed, 29 Jun 2022 09:37:52 +0000 Eric Dumazet wrote:
> syzbot reported a hang in tun_napi_disable() while RTNL is held.
> 
> Because tun.c logic is complicated, I chose to:
> 
> 1) rename tun->napi_enabled to tun->napi_configured
> 
> 2) Add a new boolean, tracking if tun->napi is enabled or not.

Not a huge surprise TBH :S

Is there a repro?