Re: [PATCH net-next v2 0/2] selftests: drv-net: so_txtime: trivial fixes

[Jakub Kicinski <kuba@kernel.org>]

On Tue, 09 Jun 2026 22:48:34 -0400 Willem de Bruijn wrote:
> Willem de Bruijn wrote:
> > Jakub Kicinski wrote:  
> > > I noticed that so_txtime is only passing on NIPA setups which are
> > > looped within a single host. The cross-machine cases just flat out
> > > fail. The initial bug is obvious - the test does not deploy the binary.
> > > But even with that I think more work would be needed to sync the
> > > time / adjust the expectations for a dual-machine test.
> > > 
> > > Willem promised to follow up on the fundamental issues with 2-host
> > > setups :)  
> > 
> > Yep.  
> 
> With these fixes the tests run fine manually on a non-dbg kernel.
> 
> The CI failures are on the netdev-X710-dbg remote only, correct?
> 
> https://netdev.bots.linux.dev/flakes.html
> https://netdev.bots.linux.dev/contest.html?executor=hwksft-X710-dbg&test=so-txtime-py
> 
> Those flakes all have a delivery later than expected, e.g.,
> 
>     # # Exception|   STDERR: payload:a delay:30747 expected:0 (us)
>     # # Exception|           exceeds variance (4000 us)
> 
> Does this remote have KSFT_MACHINE_SLOW set? This should only result in error
> 
> From contest/remote/lib/vm.py on nipa.git:
> 
>         slowdown = self.config.getfloat('vm', 'slowdown', fallback=0)
>         if slowdown:
>             self.cmd("export KSFT_MACHINE_SLOW=yes")
> 
> But I don't know where (or whether) I can review this config.

Ah, that's probably buggy. You can sort-of see the config written
dynamically here 
https://netdev.bots.linux.dev/logs/hwksft/X710-dbg/results/684641/deploy

I will fix the SLOW part, but I don't think that's the main problem, if
you look at
https://netdev.bots.linux.dev/devices.html
the X710-dbg is actually the only setup that had enough passes to
qualify as test supported. The blue cases mean that for most of the
other NICs half of the test cases fail. X710 non-debug probably dies
because we're waiting for a fix to a NAPI deadlock an earlier test
triggers, ignore it.