Re: Add a helper function in PCI IOV to get VF device

From: Chris Wright
Date: Tue Jun 08 2010 - 18:13:51 EST

* Frank Pan (frankpzh@xxxxxxxxx) wrote:
> > VF is often loaded on the physical machine.  There's also a networking
> > specific mechanism for querying and configuring a VF via the PF.
> ? I don't really understand. What do you mean load? I don't think
> physical machine is able to use it as a hardware device.

Yes, it is possible. Your example of igb...igbvf driver can be loaded
on physical machine and drive a VF instance. In fact, this is a pretty
normal mode for KVM.

> > While your patch is simple, it's unclear to me what your end goal is.
> > The patch itself only adds a function. if you showed how you are
> > planning to use it, that would really help.
> Currently my hack is applied on 2.6.18 because of xen's limitation. As
> Mitch says, igb driver is significantly different with recent ones. On
> the other hand, my hack just exposes several PCI configuration and
> MMIO registers to the sysfs, you will only understand the use case
> when you also see the userspace hacks.

OK, but this sounds like the wrong approach. We already have a
mechanism for using the PF to program a VF. Have a look at the netlink
interface. Specifically, do_setvfinfo().

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at