Re: [dpdk-dev] [PATCH v2 0/3] vhost: disable iommu support by default

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 11/07/2017 12:08 PM, Kavanagh, Mark B wrote:
>> From: Maxime Coquelin [mailto:maxime.coquelin@redhat.com]
>> Sent: Tuesday, November 7, 2017 11:05 AM
>> To: Kavanagh, Mark B <mark.b.kavanagh@intel.com>; dev@dpdk.org;
>> yliu@fridaylinux.org; thomas@monjalon.net; ktraynor@redhat.com
>> Subject: Re: [PATCH v2 0/3] vhost: disable iommu support by default
>>
>> Hi Mark,
>>
>> On 11/07/2017 11:56 AM, Kavanagh, Mark B wrote:
>>>> From: Maxime Coquelin [mailto:maxime.coquelin@redhat.com]
>>>> Sent: Monday, November 6, 2017 8:38 PM
>>>> To: dev@dpdk.org; yliu@fridaylinux.org; Kavanagh, Mark B
>>>> <mark.b.kavanagh@intel.com>; thomas@monjalon.net; ktraynor@redhat.com
>>>> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
>>>> Subject: [PATCH v2 0/3] vhost: disable iommu support by default
>>>>
>>>> This series disables IOMMU feature by default, and introduce
>>>> a new flag passed at vhost device registration time to enable
>>>> it explicitly.
>>>>
>>>> When disabled, patch 1 also disables reply-ack protocol feature
>>>> to avoid Qemu v2.7.0-v2.9.0 reply-ack bug with multiqueue.
>>>>
>>>> Last patch adds a Vhost PMD "iommu-support" parameter to enable
>>>> the IOMMU feature.
>>>
>>> Hi Maxime,
>>>
>>> I'm happy to confirm that this patchset resolves the vhost user mutltiq
>> issue for OvS-DPDK, with QEMU v2.7.1.
>>
>> Thanks for the testing.
>>
>>> Additionally, all of the individual patches look good - thanks for all of
>> your efforts on this!
>>
>> Great.
>> Now, what is required on OVS side is the introduction of a new vhost
>> port option to enable IOMMU support, so that management layer has a way
>> to enable it when VM has an iommu placed in front of the virtio device.
> 
> Sounds good - I can add this as part of the DPDK v17.11 upgrade patch :)

Thanks :) Please add me in cc when you'll post the change, so that I can
keep track of it.

Regards,
Maxime
> Thanks again,
> Mark
> 
> 
>>
>> Note that OVS can set the flag even if no IOMMU is present, as Virtio
>> feature negotiation will manage this.
>>
>>> Tested-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
>>> Acked-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
>>
>> Thanks,
>> Maxime
>>
>>> Cheers,
>>> Mark
>>>
>>>>
>>>> Maxime Coquelin (3):
>>>>    vhost: disable reply-ack protocol feature if iommu feature disabled
>>>>    vhost: add flag to enable iommu support
>>>>    net: vhost: add iommu-support parameter to enable IOMMU feature
>>>>
>>>> doc/guides/nics/vhost.rst              |  5 +++++
>>>> doc/guides/prog_guide/vhost_lib.rst    | 14 ++++++++++++++
>>>> doc/guides/rel_notes/release_17_11.rst |  3 ++-
>>>> drivers/net/vhost/rte_eth_vhost.c      | 13 +++++++++++++
>>>> lib/librte_vhost/rte_vhost.h           |  1 +
>>>> lib/librte_vhost/socket.c              |  6 ++++++
>>>> lib/librte_vhost/vhost_user.c          | 24 ++++++++++++++++++++++--
>>>> 7 files changed, 63 insertions(+), 3 deletions(-)
>>>>
>>>> --
>>>> 2.13.6
>>>