ReadOnly templates and DNS broken today after latest update

Updated last week and just today.
DNS broke today.
Can use resolvectl query local.machine.lan from both sys-net and sys-firewall. Also
ping google.com works from sys-*.

AppVms DNS fail but I can manually add
resolvectl dns eth0 10.139.1.1
and DNS works until restart of app vm.

[root@dom0 ~]# dmesg --ctime | egrep '(deferring g.e.)' |wc
   4189   41890  256038
[root@dom0 ~]# dmesg --ctime | egrep '(deferring g.e.)' | egrep '20:35:43' | wc
     64     640    3932

deferring g.e. 0x… (pfn 0x…) messages flooding all VMs #7359 https://github.com/QubesOS/qubes-issues/issues/7359

Right clicking the template and choosing update now errors saying Read Only filesystem.

From “Qube Manager”, right clicking “fedora-34” TemplateVM, and choosing “update” results in a error writing to /var/log/dnf.log and a ReadOnly filesystem error.

[root@fedora-34 etc]# mount -o remount,rw /dev/mapper/dmroot /

And without shutting down the template, I can successfully choose update from within the “Qube Manager” which does not find any updates … “Nothing to do”.

Several months ago, I had added a /proc/xen mount point in /etc/fstab. It did not seem to bother anything until today. Remounting the template rw and sudo vi /etc/fstab to remove /proc/xen line and
it most everything seems ok.
Wont be able to modify /etc/fstab until the / is remounted ReadWrite.

    bash-5.1#  **mount | egrep '(ro,)'**
    /dev/xvda3 on / type ext4 (**ro**,relatime)
    bash-5.1# **mount -o remount,rw /dev/xvda3 /**
    bash-5.1#  vi /etc/fstab   #comment out line with /proc/xen, :w to save

deferring g.e. 0x20d (pfn 0x67c46) occurs more than once-per-second. Does not seem to be hurting things, but i do not like it.

/etc/fstab, resolvectl, resolveconf, readonly filesystem,

If you see DNS issues with the recent fedora-35 update, follow :

See :