Subject: Re: [PATCH net-next 3/3] selftests: drv-net: iou-zcrx: allocate hugepages for large chunks test

From: Jakub Kicinski <[email-masked]>
Date: Mon, 2 Mar 2026 18:22:22 -0800

On Mon, 2 Mar 2026 16:16:38 +0100 Dragos Tatulea wrote:
> > +    hp_file = "/proc/sys/vm/nr_hugepages"
> > +    with open(hp_file, 'r+', encoding='utf-8') as f:
> > +        nr_hugepages = int(f.read().strip())
> > +        if nr_hugepages < 64:
> > +            f.seek(0)
> > +            f.write("64")
> > +            defer(lambda: open(hp_file, 'w', encoding='utf-8').write(str(nr_hugepages)))
> > +
> >      single(cfg)
> >      rx_cmd = f"{cfg.bin_local} -s -p {cfg.port} -i {cfg.ifname} -q {cfg.target} -x 2"
> >      tx_cmd = f"{cfg.bin_remote} -c -h {cfg.addr_v['6']} -p {cfg.port} -l 12840"
> >  
> >      probe = cmd(rx_cmd + " -d", fail=False)
> >      if probe.ret == SKIP_CODE:
> > -        raise KsftSkipEx(probe.stdout)
> > +        raise KsftSkipEx(probe.stdout.strip())
> >    
> While working on a similar fix I found that the probe here also requires a barrier.

Hm, I'm not hitting this issue. Maybe because I'm testing in QEMU?
If you can still repro after this series could you send a follow up?