Hi Adrian, Thanks for your feedback.
On 4/16/21 9:28 AM, Adrian Moreno wrote: > > > On 3/18/21 11:35 PM, Maxime Coquelin wrote: >> This patch adds vDPA device config space requests support. >> For now, it only adds MAC address get and set. It may be >> extended in next revision to support other configs like >> link state. >> >> Regarding the MAC selection strategy, if devargs MAC address >> is set by the user and valid, the driver tries to store it >> in the device config space, then it reads the MAC address >> back from the device config, which will be used. If not set >> in devargs or invalid, it tries to read it from the device. >> If it fails, a random MAC will be used. >> >> I'm interrested to know your feedback on this strategy. > > In general, I think it's a reasonable strategy. Once we have cq support, > things > will be a bit easier. > > Some questions: > How should we interpret failure to configure the mac (i.e: after set and get, > they still don't match)? Should we fail virtio_user_dev_init if the > configuration provided by devargs is not successfully applied? > > Should a zero mac be treated differntly as qemu does? [1] > > [1] > https://patchwork.ozlabs.org/project/qemu-devel/patch/20210302142014.141135-3-...@redhat.com/ Testing with ConnectX-6 Dx, I can see that the device does not advertise VIRTIO_NET_F_MAC, so with this is series, it just doesn't try to read it from the device. My understanding is that in Qemu, the feature is forced[0], which explains why it reads zeroes. > >> It has been tested with vDPA simulator, which only supports >> getting the MAC address, and witch CX6 which supports neither >> getting or setting MAC address (and so devarg or random MAC is >> used). IFCVF driver seems to support both getting and setting >> the MAC, I have a try with it before next revision. > > Does cx6 negotiate VIRTIO_NET_F_MAC? Nope. I haven't tested yet with IFCVF. Maxime >> >> Maxime Coquelin (3): >> net/virtio: keep device and frontend features separated >> net/virtio: add device config support to vDPA >> net/virtio: add MAC device config getter and setter >> >> drivers/net/virtio/virtio_user/vhost.h | 3 + >> drivers/net/virtio/virtio_user/vhost_vdpa.c | 69 +++++++++++++++ >> .../net/virtio/virtio_user/virtio_user_dev.c | 88 +++++++++++++++---- >> .../net/virtio/virtio_user/virtio_user_dev.h | 2 + >> drivers/net/virtio/virtio_user_ethdev.c | 12 ++- >> 5 files changed, 151 insertions(+), 23 deletions(-) >> > [0]: https://elixir.bootlin.com/qemu/latest/source/hw/net/virtio-net.c#L3078
