From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nikita Kalyazin <n.kalyazin@samsung.com>
Subject: Re: [PATCH v5 resend 07/12] virtio: resolve for control
 queue
Date: Fri, 09 Oct 2015 10:11:02 +0300
Message-ID: <20151009071102.GC21145@kalyazin.rnd.samsung.ru>
References: <1442589061-19225-1-git-send-email-yuanhan.liu@linux.intel.com>
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 <5616D736.2040108@steffenbauch.de>
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To: Steffen Bauch <mail@steffenbauch.de>
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Hi,

> I just recognized that this dead loop is the same one that I have 
> experienced (see 
> http://dpdk.org/ml/archives/dev/2015-October/024737.html for reference). 
> Just applying the changes in this patch (only 07/12) will not fix the 
> dead loop at least in my setup.
Yes, exactly. I observe it same way even after applying the patch.

-- 

Best regards,

Nikita Kalyazin,
n.kalyazin@samsung.com

Software Engineer
Virtualization Group
Samsung R&D Institute Russia
Tel: +7 (495) 797-25-00 #3816
Tel: +7 (495) 797-25-03
Office #1501, 12-1, Dvintsev str.,
Moscow, 127018, Russia

On Thu, Oct 08, 2015 at 10:51:02PM +0200, Steffen Bauch wrote:
> 
> 
> On 10/08/2015 05:32 PM, Nikita Kalyazin wrote:
> > Hi Yuanhan,
> >
> >
> > As I understand, the dead loop happened here (virtio_send_command):
> > while (vq->vq_used_cons_idx == vq->vq_ring.used->idx) {
> >        rte_rmb();
> >        usleep(100);
> > }
> >
> > Could you explain why wrong config reading caused that and how correct reading helps to avoid?
> >
> Hi,
> 
> I just recognized that this dead loop is the same one that I have 
> experienced (see 
> http://dpdk.org/ml/archives/dev/2015-October/024737.html for reference). 
> Just applying the changes in this patch (only 07/12) will not fix the 
> dead loop at least in my setup.
> 
> Best regards,
> 
> Steffen