annual howto rampage

[Greg Troxel <gdt%lexort.com@localhost>]

I often edit the howto in late december.  Now is very late december 2023 ;-)

I have gc'd info about NetBSD 8, and the mention of xm.

Specific things I'd like comments on (onlist please, either to check
consensus or because I think others will think the useful/message ratio
is high enough):

  - Are there any problems with 4.15?

  - Are there any problems with 4.18 (other than timekeeping)?

  - Have we crossed over to 4.18 being the standard approach, and 4.15
    old?  (I think so but don't want to say that without asking.)

Absent comments, I will adjust to say both 4.15 and 4.18 work, modulo
4.18 timekeeping, and that 4.18 is the standard apparoch.

Further for the list:

  - Is anyone working on newer xen?

  - Is the problem with i386 PV guests under 4.18 about all PV, or just
    NetBSD?


And offlist is fine for things to add/update but not so likely controversial or
useful to others:

  - URL for PR about timekeeping?

  - Can one now boot a NetBSD dom0 via UEFI?  If so, is there anything
    tricky?  If not, is there a PR?

  - Is it true that PVH and PVHVM both also require VT-X/SVM just like HVM?

  - Still true?
      Operation of i386 PVH guests is not reliable.
      See [PR 57199](https://gnats.netbsd.org/57199).

  - Do we know the hypervisor version that is troubled about the 33rd
    grant table entry?
    http://gnats.netbsd.org/58395



(And, I have a system I can crash as a 4G dom0 but not as an 8G bare
metal kernel, via zfs, but I think that's about 4G vs 8G and not about
xen, at least so far.  But if you are struggling with this also, please
let me know, privately or onlist.)