This series of patches provides the ability to retrieve eBPF program
through qmp, so management application may load bpf blob with proper capabilities.
Now, virtio-net devices can accept eBPF programs and maps through properties
as external file descriptors. Access to the eBPF map is direct through mmap()
call, so it should not require additional capabilities to bpf* calls.
eBPF file descriptors can be passed to QEMU from parent process or by unix
socket with sendfd() qmp command.

Possible solution for libvirt may look like this: https://github.com/daynix/libvirt/tree/RSS_eBPF (WIP)

Andrew Melnychenko (5):
  ebpf: Added eBPF initialization by fds and map update.
  virtio-net: Added property to load eBPF RSS with fds.
  ebpf: Added declaration/initialization routines.
  qmp: Added new command to retrieve eBPF blob.
  ebpf: Updated eBPF program and skeleton.

 ebpf/ebpf.c                    |   54 ++
 ebpf/ebpf.h                    |   31 +
 ebpf/ebpf_rss-stub.c           |    6 +
 ebpf/ebpf_rss.c                |  124 ++-
 ebpf/ebpf_rss.h                |   10 +
 ebpf/meson.build               |    1 +
 ebpf/rss.bpf.skeleton.h        | 1469 ++++++++++++++++----------------
 hw/net/virtio-net.c            |   96 ++-
 include/hw/virtio/virtio-net.h |    1 +
 monitor/qmp-cmds.c             |   16 +
 qapi/misc.json                 |   28 +
 tools/ebpf/rss.bpf.c           |    2 +-
 12 files changed, 1079 insertions(+), 759 deletions(-)
 create mode 100644 ebpf/ebpf.c
 create mode 100644 ebpf/ebpf.h

-- 
2.39.1

On Mon, May 01, 2023 at 10:20:56AM +0300, Andrew Melnychenko wrote:
> This series of patches provides the ability to retrieve eBPF program
> through qmp, so management application may load bpf blob with proper capabilities.
> Now, virtio-net devices can accept eBPF programs and maps through properties
> as external file descriptors. Access to the eBPF map is direct through mmap()
> call, so it should not require additional capabilities to bpf* calls.
> eBPF file descriptors can be passed to QEMU from parent process or by unix
> socket with sendfd() qmp command.
> 
> Possible solution for libvirt may look like this: https://github.com/daynix/libvirt/tree/RSS_eBPF (WIP)

Is that complete enough to be running guests ? If so, have you
successfully tested with a QEMU running under qemu:///system
as the qemu:qemu user, to prove it works without any extra
capabilities being needed ?

With regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|

Hi all,

On Wed, May 3, 2023 at 11:22 AM Daniel P. Berrangé <berrange@redhat.com> wrote:
>
> On Mon, May 01, 2023 at 10:20:56AM +0300, Andrew Melnychenko wrote:
> > This series of patches provides the ability to retrieve eBPF program
> > through qmp, so management application may load bpf blob with proper capabilities.
> > Now, virtio-net devices can accept eBPF programs and maps through properties
> > as external file descriptors. Access to the eBPF map is direct through mmap()
> > call, so it should not require additional capabilities to bpf* calls.
> > eBPF file descriptors can be passed to QEMU from parent process or by unix
> > socket with sendfd() qmp command.
> >
> > Possible solution for libvirt may look like this: https://github.com/daynix/libvirt/tree/RSS_eBPF (WIP)
>
> Is that complete enough to be running guests ? If so, have you
> successfully tested with a QEMU running under qemu:///system
> as the qemu:qemu user, to prove it works without any extra
> capabilities being needed ?

Yeah, but still working on it. Overall, QEMU doesn't require
additional capabilities.
Map update through mmap doesn't require any.
Tested with qemu://system.
There is still an issue with cache for libvirt.

>
> With regards,
> Daniel
> --
> |: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
> |: https://libvirt.org         -o-            https://fstop138.berrange.com :|
> |: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|
>