Re: [RFC] test/eal_flags: suppress vdev_netvsc auto-probe

[Stephen Hemminger <stephen@networkplumber.org>]

On Mon, 23 Feb 2026 17:00:11 +0000
Bruce Richardson <bruce.richardson@intel.com> wrote:

> On Sun, Feb 22, 2026 at 06:49:44PM -0800, Stephen Hemminger wrote:
> > On Sun, 22 Feb 2026 14:15:42 -0800
> > Stephen Hemminger <stephen@networkplumber.org> wrote:
> >   
> > > On Hyper-V systems (including Azure-hosted CI), the vdev_netvsc
> > > driver auto-injects itself during vdev bus scan. This interferes
> > > with the vdev flag test causing the nodeaction subprocess to fail.
> > > 
> > > Suppress by passing net_vdev_netvsc,ignore=1 in the valid vdev
> > > test cases. The scan callback sees it already in devargs and
> > > skips injection; the probe honours ignore and does nothing.
> > > 
> > > Fixes: 0d684a783088 ("app/test: fix and separate --vdev unit test")
> > > Cc: stable@dpdk.org
> > > 
> > > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>  
> > 
> > Self NAK
> > 
> > This is not the underlying cause of the test failures.
> > The issue is likely parallel test invocation overlapping on the file prefix
> > which is already addressed by another pending patch series.
> > 
> > That said, something should be done about vdev_netvsc driver and github
> > interactions.  
> 
> I don't think it's parallel invocations - we don't run our unit tests in
> parallel in github actions. I'd also note that the current issues started
> appearing when we patched in support to pass through the drivers path to
> the secondary process calls so that they could match the primary instance.
> Therefore, I still suspect something in the pci or other bus scanning to be
> a problem. Do we need to disable the netvsc as in your patch and also pass
> in --no-pci to the test cases?
> 
> /Bruce

I am thinking that vdev_netvsc driver hack needs to have a way
of detecting whether it is being run in a test. Maybe getenv("DPDK_TEST")
or some other github detection.