[dpdk-dev] [PATCH] vfio: support iommu group zero

[Thomas Monjalon]

2015-12-09 09:55, Stephen Hemminger:
> The current implementation of VFIO will not with the new no-IOMMU mode
> in 4.4 kernel. The original code assumed that IOMMU group zero would
> never be used. Group numbers are assigned starting at zero, and up
> until now the group numbers came from the hardware which is likely
> to use group 0 for system devices that are not used with DPDK.
> 
> The fix is to allow 0 as a valid group and rearrange code
> to split the return value from the group value.
> 
> Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
> ---
> Why was this ignored? It was originally sent on 26 Oct 15 back
> when IOMMU discussion was lively.

There was no review of this patch.
The patch has been marked as deferred recently when it was too late
to do such feature changes in DPDK code:
	http://dpdk.org/dev/patchwork/patch/8035/

So I guess you have tested the VFIO no-iommu patch.
Is it working well with DPDK with only this patch for group zero?
Have you talked to Alex Williamson?
He was requesting some feedbacks:
	http://dpdk.org/ml/archives/dev/2015-December/029291.html

Thanks