On Thu, Jan 10, 2008 at 02:43:02PM +0100, Christoph Egger wrote:
> > What is the "PIT timer" ?
> 
> the i8254 thingy.
> 
> I get a series of endless xen messages:
> 
> (XEN) i8254.c:534:d1 PIT bad access
> (XEN) i8254.c:534:d1 PIT bad access
> (XEN) i8254.c:534:d1 PIT bad access
> (XEN) i8254.c:534:d1 PIT bad access
> (XEN) i8254.c:534:d1 PIT bad access
> 
> The message comes from Xen in xen/arch/x86/hvm/i8254.c,

Ha OK, it's on a HVM guest. 
I guess the relevant NetBSD code is x86/isa/clock.c

Could it be this change ?
-       low = inb(IO_TIMER1 + TIMER_CNTR0);
-       high = inb(IO_TIMER1 + TIMER_CNTR0);
-       count = rtclock_tval - ((high << 8) | low);
-
+       /* insb to make the read atomic */
+       insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
+       count = rtclock_tval - rdval;

>     if ( (p->size != 1) || p->data_is_ptr || (p->type != IOREQ_TYPE_PIO) )
>     {
>         gdprintk(XENLOG_WARNING, "PIT bad access\n");
>         return 1;
>     }
> 
> p->data_is_ptr is 1.
> 
> > I've no problems booting 4.99.48 on Xen 3.1.2 
> 
> Did you try NetBSD as PV or HVM guest?
> 
> I'm using Xen 3.2.0-rc5 and NetBSD/amd64 as HVM guest.
> 
> NetBSD as PV guest almost works nice.
> When I boot the install kernel and shut it down with "halt -p",
> then I get a panic in mfs_close():
> 
> # halt -p
> syncing disks... done
> unmounting file systems...
> unmounting /kern (kernfs)...
> unmounting /dev (mfs:10)...mfs_close: ref count 2 > 1
> panic: mfs_close

that's not specific to Xen, I've seen reports of this on current-users.

-- 
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
     NetBSD: 26 ans d'experience feront toujours la difference
--