Re: VDPA MAC address problem

[Konstantin Shkolnyy <kshk@linux.ibm.com>]

On 3/19/2025 19:58, Jason Wang wrote:
> On Thu, Mar 20, 2025 at 12:34 AM Konstantin Shkolnyy <kshk@linux.ibm.com> wrote:
>> Upon reading this forum, I see that VHOST_VDPA_SET_CONFIG is
>> “deprecated”, and so VIRTIO_NET_CTRL_MAC_ADDR_SET must be the right
>> method, but it’s apparently called too late.
> 
> VHOST_VDPA_SET_CONFIG requires the vDPA parent support which is not
> necessarily there.

The mlx5 driver doesn't do anything for VHOST_VDPA_SET_CONFIG. Intel's 
driver, however, apparently stores the configuration. So, it appears, 
Intel will avoid the problem... Perhaps mlx5 could do the same so that 
QEMU can set the address before it starts the VM (QEMU doesn't have to 
later let the VM change the config). Conceptually, setting the address 
by QEMU cmdline doesn't look different from setting it by "vdpa dev add".