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

[Maxime Coquelin]

Hi Mark,

On 11/07/2017 11:56 AM, Kavanagh, Mark B wrote:
>> From: Maxime Coquelin [mailto:maxime.coquelin at redhat.com]
>> Sent: Monday, November 6, 2017 8:38 PM
>> To: dev at dpdk.org; yliu at fridaylinux.org; Kavanagh, Mark B
>> <mark.b.kavanagh at intel.com>; thomas at monjalon.net; ktraynor at redhat.com
>> Cc: Maxime Coquelin <maxime.coquelin at 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.

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 at intel.com>
> Acked-by: Mark Kavanagh <mark.b.kavanagh at 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
>