From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Fedin <p.fedin@samsung.com>
Subject: Re: [PATCH 0/4 for 2.3] vhost-user live migration support
Date: Wed, 16 Dec 2015 14:57:15 +0300
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Cc: dev@dpdk.org, 'Victor Kaplansky' <victork@redhat.com>
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 Hello!

> I can reproduce your issue on my side with above patch (and only when
> F_GUEST_ANNOUNCE is not set at DPDK vhost lib). TBH, I don't know
> why that happened, the cause could be subtle, and I don't think it's
> worthwhile to dig it, especially it's not the right way to do it.

 May be not right, may be it can be done... Actually, i found what was wrong. qemu tries to feed features back to vhost-user via
VHOST_USER_SET_FEATURES, and DPDK barfs on the unknown bit. More tweaking is needed for qemu to do the trick correctly.

> So, would you please try to set the F_GUEST_ANNOUNCE flag on DPDK vhost
> lib side, as my early diff showed and have another test?

 Tried it, works fine, thank you.
 I have almost implemented the workaround in qemu... However now i start to think that you are right. Theoretically, the application
may want to suppress GUEST_ANNOUNCE for some reason. So, let it stay this way. Please include this bit into your v2.

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia