xen discuss - Sep 2007 - Re: NetBSD 3.1 HVM domU hangs... [was Re: nvidia driver incompatible with snv_75 xen putback?]

> So it seems the NetBSD domU is receiving lots of floppy controller
> IRQ#6 interrupts (trap == 0x26), and is accessing the 8259 interrupt
> controller (PIC) I/O ports 0x20 and 0x21. Somehow it is unable to clear
> the IRQ#6 condition, it seems (I don''t see floppy controller I/O
> port accesses at all?).
> 
> 
> Apparently this is a known problem with NetBSD under Xen HVM:
> 
> http://mail-index.netbsd.org/port-xen/2007/08/29/0002.html
> http://mail-index.netbsd.org/port-xen/2007/09/07/0000.html

The above thread contains a hint for a workaround:  Disable
netbsd''s floppy controller driver fdc.  This works by booting
netbsd with "boot -c",  then using the commands "disable
fdc"
and "quit" at the "uc>" prompt.

Now the NetBSD 3.1 kernel starts in a HVM domU, without hanging
the guest domain (under snv66 dom0)...