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Date: Fri, 25 Jan 2019 13:44:45 +0100
From: Jens Freimann <jfreimann@redhat.com>
To: Ilya Maximets <i.maximets@samsung.com>
Cc: dev@dpdk.org, Maxime Coquelin <maxime.coquelin@redhat.com>,
 "Michael S . Tsirkin" <mst@redhat.com>, Tiwei Bie <tiwei.bie@intel.com>,
 Zhihong Wang <zhihong.wang@intel.com>, stable@dpdk.org
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 (mx1.redhat.com [10.5.110.39]); Fri, 25 Jan 2019 12:45:01 +0000 (UTC)
Subject: Re: [dpdk-stable] [PATCH 3/3] net/virtio: add missing read barrier
 for packed dequeue
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On Thu, Jan 24, 2019 at 07:59:02PM +0300, Ilya Maximets wrote:
>Read barrier is required between reading the flags (desc_is_used)
>and the content of descriptor to ensure the ordering.
>Otherwise, speculative read of desc.id could be reordered with
>reading of the desc.flags.
>
>Fixes: a76290c8f1cf ("net/virtio: implement Rx path for packed queues")
>Cc: stable@dpdk.org
>
>Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
>---
> drivers/net/virtio/virtio_rxtx.c | 1 +
> 1 file changed, 1 insertion(+)
>

Reviewed-by: Jens Freimann <jfreimann@redhat.com>