Re: iwn failure on -current (XEN3_DOM0)

[Chavdar Ivanov <ci4ic4%gmail.com@localhost>]

On 19 November 2017 at 08:01, Michael van Elst <mlelstv%serpens.de@localhost> wrote:
> ci4ic4%gmail.com@localhost (Chavdar Ivanov) writes:
>
>>I used to run DOM0 on xen4.8, the wireless interface worked for the
>>DOM0, although I could never make the bridge work (it worked with the
>>wired wm0, though).
>
> You cannot bridge via WiFi because this requires support to not
> only receive for arbitrary MAC addresses but also to send from
> them.

This isn't obvious for anyone using bridged over wifi VirtualBox or
VMWare Workstation machines, but I see now the host takes care of
this, as the arp table of the destination has of course the mac
address of the host interface on all the bridged guests. Again, this
must have been obvious, but I've used it without much thinking.

>
> Some hardware might even allow that (it's necessary for hostap
> mode), but then you need to act as multiple WiFi clients. Then
> there is WDS mode (also known as 4-address mode), that lets you
> act as a WiFi extender, but we don't support that either, it's also
> not compatible with many access points.

In theory at least, if that could be done on a Type 2 hypervisor, it
could be done for Xen as well, although I admit that the usage
scenarios are not compelling for the effort.

>
>
>>iwn0: timeout waiting for adapter to initialize
>
> I'm not sure how far PCI passthrough does work with NetBSD.

Here my point was that iwn used to work under XEN3_DOM0 a few months
ago and is not working now, which may indicate some problem or
regression elsewhere, which was the main reason for my question. By
the way, speedtest.net maybe a lame way to test a wifi connection, but
on mine (200mb/s cable) connection, running -current with iwn gives me
about 23mb/s, whereas on the same hardware / dns / router etc. some
Linux gives me about 57 mb/s ( I do get my full about 212mb/s when
running the test over AC7275 wifi from my W10 laptop, so it is not the
infrastructure, with the possible exception that NetBSD runs off a
HDD, whereas the Linux distro off an SSD, but that probably doesn't
matter here. ).

>
> --
> --
>                                 Michael van Elst
> Internet: mlelstv%serpens.de@localhost
>                                 "A potential Snark may lurk in every tree."

Thanks for the info. I do have another laptop using a wired connection
(and much more suitable for Xen, with an SSD, 20GB memory and a 4c/8t
cpu), so the problem was moot anyway.

Chavdar Ivanov

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