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Date: Mon, 1 Aug 2011 13:26:43 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Liu Yuan <namei.unix@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>, Avi Kivity <avi@redhat.com>,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH] vhost-blk: An in-kernel accelerator for virtio-blk
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On Mon, Aug 01, 2011 at 04:55:54PM +0800, Liu Yuan wrote:
> Nope, V1 completion thread doesn't has any mutex, thus can run
> parallel with the vhost worker.

It's true, it doesn't, but I think it's a bug :)
It calls vhost_add_used which definitely needs the
vq mutex.