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Date: Mon, 16 Jul 2018 11:28:23 +0200
From: Igor Mammedov <imammedo@redhat.com>
Message-ID: <20180716112823.0b8925d0@redhat.com>
In-Reply-To: <20180716083732.3347-1-stefanha@redhat.com>
References: <20180716083732.3347-1-stefanha@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 0/2] virtio-scsi: fix hotplug ->reset()
 vs event race
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To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, l00284672 <lizhengui@huawei.com>, Fam Zheng <famz@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>

On Mon, 16 Jul 2018 09:37:30 +0100
Stefan Hajnoczi <stefanha@redhat.com> wrote:

> v2:
>  * Drop Error **errp argument to post_plug() handler [Paolo]
>  * Move post_plug() call outside if (dev->hotplugged)
> 
> The virtio-scsi command virtqueues run during hotplug.  This creates the
> possibility of race conditions since the guest can submit commands while the
> monitor is performing hotplug.
> 
> See Patch 2 for a fix for the ->reset() vs event race condition that Zhengui Li
> encountered.
> 
> Stefan Hajnoczi (2):
>   qdev: add HotplugHandler->post_plug() callback
>   virtio-scsi: fix hotplug ->reset() vs event race
> 
>  include/hw/hotplug.h  | 11 +++++++++++
>  hw/core/hotplug.c     | 10 ++++++++++
>  hw/core/qdev.c        |  4 ++++
>  hw/scsi/virtio-scsi.c | 11 ++++++++++-
>  4 files changed, 35 insertions(+), 1 deletion(-)
> 

Reviewed-by: Igor Mammedov <imammedo@redhat.com>