Re: [Qemu-devel] [PATCH v3 for-1.7] rdma: rename 'x-rdma' => 'rdma'

[Michael R. Hines]

On 11/15/2013 12:06 PM, Daniel P. Berrange wrote:
> On Wed, Nov 06, 2013 at 01:59:14PM -0500, address@hidden wrote:
> > From: "Michael R. Hines" <address@hidden>
> >
> > As far as we can tell, all known bugs have been fixed:
> [snip]
>
> > 3. Libvirt patches are ready
> [snip]
>
> > Objections?
> There was a first round of patches posted to the libvirt list back
> in July, but those were rejected since QEMU side was still in flux.

Yes, I'm addressing all the reviews I received back in July,
I just haven't posted them to the list yet - stay tuned.

> More seriously though, from discussions at the KVM Forum it sounds
> like there is a significant problem in actually using the RDMA
> code. Unfortunately I can't remember who I was talking with about
> it, but I was told that it requires the QEMU process to run as root
> in order to talk to some of the kernel interfaces, and requires
> manual updates to the cgroups device ACL to allow QEMU access to
> some RMDA related device nodes.

No, that was for Fault Tolerance, not for RDMA specifically.

You were speaking to me =). The jog your memory, the issue
was related to the need by Micro-Checkpointing to access
netlink sockets to interact properly with netlink in the kernel.

This is unrelated to RDMA - accessing the /dev/infiniband
device nodes is already supported by libvirt my modifying
the configuration file in /etc and that works just fine.

- Michael