kern/148262: [xen] [panic] HYPERVISOR_update_va_mapping

[Jung-uk Kim]

On Saturday 02 October 2010 09:43 am, Juergen Lock wrote:
> [kern/149853 is a duplicate of this]
>
> I don't use xen myself here but I helped someone on irc
> troubleshoot the same crash (before I saw these PRs), and found out
> the reason it didn't happen on 8.0 is the x86bios code is new in
> 8.1 and xen doesn't like this call in x86bios_map_mem():
>
> 	x86bios_ivt = pmap_mapbios(X86BIOS_IVT_BASE, X86BIOS_IVT_SIZE);
>
> see:
>
> 	http://fxr.watson.org/fxr/source/compat/x86bios/x86bios.c?v=FREEBS
>D8#L498
>
> It seems the only consumers of x86bios are atkbd(4), dpms(4), and
> vesa(4), and indeed removing atkbd(4) from the xen kernel got his
> domU running.
>
> (And now that I just looked at /sys/i386/conf/XEN in svn I see this
> was already fixed in r204157, it only never got MFCd.)

Can you please revert r204157 and test -CURRENT?  It shouldn't 
necessary because HEAD uses vm86 as a backend for i386 now.

Thanks!

Jung-uk Kim