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Date:   Tue, 24 Nov 2020 09:31:37 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Jason Wang <jasowang@redhat.com>
Cc:     Jakub Kicinski <kuba@kernel.org>,
        Leon Romanovsky <leon@kernel.org>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Petr Mladek <pmladek@suse.com>,
        John Ogness <john.ogness@linutronix.de>,
        virtualization@lists.linux-foundation.org,
        Amit Shah <amit@kernel.org>, Itay Aveksis <itayav@nvidia.com>,
        Ran Rozenstein <ranro@nvidia.com>,
        netdev <netdev@vger.kernel.org>
Subject: Re: netconsole deadlock with virtnet
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On Tue, 24 Nov 2020 11:22:03 +0800
Jason Wang <jasowang@redhat.com> wrote:

> Btw, have a quick search, there are several other drivers that uses tx 
> lock in the tx NAPI.

tx NAPI is not the issue. The issue is that write_msg() (in netconsole.c)
calls this polling logic with the target_list_lock held.

Are those other drivers called by netconsole? If not, then this is unique
to virtio-net.

-- Steve