[RFC] net/vdev_netvsc: disable auto-detection by default

[Stephen Hemminger]

On Tue, 24 Feb 2026 08:58:45 +0100
David Marchand <david.marchand at redhat.com> wrote:

> On Tue, 24 Feb 2026 at 08:41, David Marchand <david.marchand at redhat.com> wrote:
> >
> > On Tue, 24 Feb 2026 at 02:43, Stephen Hemminger
> > <stephen at networkplumber.org> wrote:  
> > >
> > > The vdev_netvsc driver auto-injects itself on Hyper-V via an
> > > RTE_INIT constructor. This interferes with tests on github actions
> > > which uses Azure where the driver probes in forked subprocesses
> > > and crashes on uninitialized interrupt instances.
> > >
> > > Guard the auto-detection behind RTE_LIBRTE_VDEV_NETVSC_AUTO
> > > (disabled by default). The driver must now be explicitly
> > > requested with --vdev=net_vdev_netvsc.
> > >
> > > Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>  
> >
> > The failure in GHA can be avoided with a simpler:
> > https://patchwork.dpdk.org/project/dpdk/patch/20260223155603.3651641-1-david.marchand@redhat.com/  
> 
> After rerunning with debug, the vdev netvsc is still probed, but is
> not at fault for the recent failures we saw.
> 
> VMBUS_BUS: vmbus_probe_one_driver(): VMBUS device
> 7c1e52d8-3f86-7c1e-52d8-3f867c1e52d8 on NUMA socket -1
> VMBUS_BUS: rte_vmbus_map_device(): Not managed by UIO driver, skipped
> VDEV_BUS: vdev_probe_all_drivers(): Search driver to probe device net_ring0
> VDEV_BUS: vdev_probe_all_drivers(): Search driver to probe device
> net_vdev_netvsc
> DPAA2_BUS: fslmc_vfio_close_group: Get fd by name((null)) failed(-19)
> DPAA2_BUS: Unable to close devices -19
> DPAA_BUS: dpaa_bus_cleanup():  >>
> DPAA_BUS: Portal already cleaned
> DPAA_BUS: dpaa_bus_cleanup(): Bus cleanup done
> Calling recursive action for test_invalid_vdev_flag
> Returned from recursive action for test_invalid_vdev_flag with 0
> Cleaning up /home/runner/work/dpdk/dpdk/build/app/dpdk-test recursive instance
> /home/runner/work/dpdk/dpdk/build/app/dpdk-test recursive instance returning 0
> Test OK
> RTE>>  

The DPAA_BUS looks like noise.
And also VMBUS.

Maybe we need a --no-bus flag that shuts off all buses?