[issue995] DFly doesnt work on Vmware and Virtualbox

[YONETANI Tomokazu]

On Sat, Sep 27, 2008 at 03:39:04AM +0200, Michael Neumann wrote:
> Hasso Tepper schrieb:
>> Hasso Tepper <hasso at estpak.ee> added the comment:
>>
>> http://permalink.gmane.org/gmane.os.netbsd.devel.cvs/116453 ?

I was under the impression that we had a TSC-based timer and could switch
via sysctl or a loader variable, but maybe I was confused, probably it's
FreeBSD 5+.

> With the following patch DragonFly runs perfectly well on VirtualBox  
> (acpi_load="YES"; VT-x/AMD-V deactivated).

Out of curiosity, does setting hw.i8254.walltimer to 1 or 2 change
the situation?

> I don't know if delta=0 is possible on a real machine and if it would do  
> harm to leave the loop in that case. If it would be harmful, I'd suggest
> to introduce a tunable virtualbox_quirk and change the patch below  
> towards this one:
>
>   if (delta == 0 && virtualbox_quirk) break;
>
> Any thoughts?

Do you need the patch only during the boot?  If so, I'd rather try to fix
the cputimer, or add one that works for VirtualBox.

Cheers.