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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Thu, 19 Apr 2018 19:35:57 +0200
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Subject: Re: [Qemu-devel] [virtio-dev] RE: [PATCH v3 6/6] vhost-user:
 support registering external host notifiers
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: "Liang, Cunming" <cunming.liang@intel.com>, "Bie, Tiwei" <tiwei.bie@intel.com>, "jasowang@redhat.com" <jasowang@redhat.com>, "alex.williamson@redhat.com" <alex.williamson@redhat.com>, "stefanha@redhat.com" <stefanha@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "virtio-dev@lists.oasis-open.org" <virtio-dev@lists.oasis-open.org>, "Daly, Dan" <dan.daly@intel.com>, "Tan,
	Jianfeng" <jianfeng.tan@intel.com>, "Wang, Zhihong" <zhihong.wang@intel.com>, "Wang, Xiao W" <xiao.w.wang@intel.com>

On 19/04/2018 19:27, Michael S. Tsirkin wrote:
> 
> That CONFIG_SMP here is clearly wrong but I don't really know what
> to set it to. Also, we probably should switch virtio_wmb to dma_XX
> barriers.
> 
> That's actually easy. Will try to do.

Should it be dma_wmb() before updating the indices, and wmb() before
writing the "kick virtqueue" register?

Paolo