Re: NetBSD dom0 PVH: hardware interrupts stalls

[Manuel Bouyer <bouyer@antioche.eu.org>]

On Mon, Nov 23, 2020 at 01:51:12PM +0100, Roger Pau Monné wrote:
> Hm, yes, it's quite weird. Do you know whether a NetBSD kernel can be
> multibooted from pxelinux with Xen? I would like to see if I can
> reproduce this myself.

Yes, if Xen+linux can boot, Xen+netbsd should boot too.
In a previous mail I wrote:
In case it helps, I put by Xen and netbsd kernels at
http://www-soc.lip6.fr/~bouyer/netbsd-dom0-pvh/
I boot it from the NetBSD boot loader with:
menu=Boot Xen PVH:load /netbsd-test console=com0 root=dk0 -vx; multiboot /xen-te
st.gz dom0_mem=1024M console=com2 com2=57600,8n1 loglvl=all guest_loglvl=all gnt
tab_max_nr_frames=64 dom0=pvh iommu=debug
I guess with grub this would be
kernel /xen-test.gz dom0_mem=1024M console=com2 com2=57600,8n1 loglvl=all guest_
loglvl=all gnttab_max_nr_frames=64 dom0=pvh iommu=debug
module /netbsd-test console=com0 root=dk0 -vx

(yes, com2 for xen and com0 for netbsd, that's not a bug :)
You can enter the NetBSD debugger with
+++++
you can then enter commands, lile
sh ev /i
to see the interrupt counters

> 
> I have the following patch also which will print a warning message
> when GSI 34 is injected from hardware or when Xen performs an EOI
> (either from a time out or when reacting to a guest one). I would
> expect at least the interrupt injection one to trigger together with
> the existing message.

It's quite verbose. I put the full log at
http://www-soc.lip6.fr/~bouyer/xen-log4.txt

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--