From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [PATCH v2] vhost: flush used->idx update before
	reading avail->flags
Date: Wed, 13 May 2015 12:46:30 +0200
Message-ID: <1907109.z7RyHoHxuq@xps13>
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To: Huawei Xie <huawei.xie@intel.com>
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2015-04-29 19:11, Huawei Xie:
> update of used->idx and read of avail->flags could be reordered.
> memory fence should be used to ensure the order, otherwise guest could see a stale used->idx value after it toggles the interrupt suppression flag.
> After guest sets the interrupt suppression flag, it will check if there is more buffer to process through used->idx. If it sees a stale value, it will exit the processing while host willn't send interrupt to guest.
> 
> Signed-off-by: Huawei Xie <huawei.xie@intel.com>

Applied with following title, thanks
	vhost: fix virtio freeze due to missed interrupt