DragonFly bugs List (threaded) for 2008-05
DragonFly BSD
DragonFly bugs List (threaded) for 2008-05
[Date Prev][Date Next]  [Thread Prev][Thread Next]  [Date Index][Thread Index]

Re: [issue995] DFly doesnt work on Vmware and Virtualbox

From: Jordan Gordeev <jgordeev@xxxxxx>
Date: Sat, 24 May 2008 22:50:17 +0300

Today, after a session of colaborative debugging, Antonio "have no clue" Huete, Jordan "doesn't run VirtualBox" Gordeev and Samuel Greear found out that the primary problem that DragonFly had on VirtualBox was caused by a non-terminating loop.
The loop is in sys/platform/pc32/isa/clock.c and starts at line 411 (on HEAD).
Forcing the loop to terminate after at most 1000 iterations causes DragonFly to successfully run with UP kernel with ACPI turned on. UP kernels with ACPI turned off and SMP kernels remain to be fixed.
In revision 1.11 of clock.c (diff to revision 1.10 at http://www.dragonflybsd.org/cvsweb/src/sys/platform/pc32/isa/clock.c.diff?r1=1.10&r2=1.1), the case in the loop body when delta < 0 was simplified, which apparently affected the loop termination condition.
The change from revision 1.10 to revision 1.11 includes the following strange change, too:

-		delta = prev_tick - tick;
+		delta = tick - prev_tick;

The FreeBSD code handling the delta values looks confused, and as the current DragonFly code fails at least on VirtualBox, I think a closer examination of the actually occurring delta values is merited.

[Date Prev][Date Next]  [Thread Prev][Thread Next]  [Date Index][Thread Index]