Re: latest amd64 XEN3_DOMU panics at boot

[Mindaugas Rasiukevicius <rmind%netbsd.org@localhost>]

Hello,

Jeff Rizzo <riz%tastylime.net@localhost> wrote:
> I assume this is because of the rmind-uvmplock branch merge, but the 
> latest amd64 domU kernel downloaded from the releng cluster panics at
> boot:
> ...

I have committed various Xen fixes.  PR/45062 should also be fixed,
or at least XEN3_DOM0 boots and works for me.  I am not sure yet why
"(pte & PG_G) == 0 || pm == pmap_kernel()" assert fails for Xen, but
see below.

Xen kernels print "pmap_kenter_pa: mapping already present" messages
during the boot and after.  While not fatal, they indicate dirty page
table entries (PTEs), which we normally should not have.  I would guess
that page tables are not zeroed somewhere.  Perhaps early boot code,
xen_pmap_bootstrap() does zeroing, but not sure if correctly.

It is not a new problem, it happens with 5.99.52 (pre uvmplock merge)
Xen kernel as well, except now diagnostic message is printed.

Thoughts?

-- 
Mindaugas