Re: [PATCH v4 00/14] Copy Offload in NVMe Fabrics with P2P PCI Memory

[Logan Gunthorpe]

On 08/05/18 10:57 AM, Alex Williamson wrote:
> AIUI from previously questioning this, the change is hidden behind a
> build-time config option and only custom kernels or distros optimized
> for this sort of support would enable that build option.  I'm more than
> a little dubious though that we're not going to have a wave of distros
> enabling this only to get user complaints that they can no longer make
> effective use of their devices for assignment due to the resulting span
> of the IOMMU groups, nor is there any sort of compromise, configure
> the kernel for p2p or device assignment, not both.  Is this really such
> a unique feature that distro users aren't going to be asking for both
> features?  Thanks,

I think it is. But it sounds like the majority want this to be a command
line option. So we will look at doing that for v5.

Logan