[issue995] DFly doesnt work on Vmware and Virtualbox

[Michael Neumann]

Hasso Tepper schrieb:
Hasso Tepper <hasso at estpak.ee> added the comment:

http://permalink.gmane.org/gmane.os.netbsd.devel.cvs/116453 ?
With the following patch DragonFly runs perfectly well on VirtualBox 
(acpi_load="YES"; VT-x/AMD-V deactivated).

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?

Regards,

  Michael

Index: clock.c
===================================================================
RCS file: /home/dcvs/src/sys/platform/pc32/isa/clock.c,v
retrieving revision 1.55
diff -u -r1.55 clock.c
--- clock.c     2 Aug 2008 01:14:43 -0000       1.55
+++ clock.c     27 Sep 2008 00:51:09 -0000
@@ -420,6 +420,8 @@
                ticks_left -= delta;
                if (doswitch && ticks_left > 0)
                        lwkt_switch();
+               if (delta == 0) break;
+
        }
 #ifdef DELAYDEBUG
        if (state == 1)