The following reply was made to PR port-xen/29999; it has been noted by GNATS.

From: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
To: bouyer@antioche.lip6.fr
Cc: gnats-bugs@NetBSD.org, port-xen-maintainer@NetBSD.org,
	gnats-admin@NetBSD.org, netbsd-bugs@NetBSD.org
Subject: Re: port-xen/29999: ctrl_if_interrupt IPL problem
Date: Tue, 19 Apr 2005 18:25:14 +0900

 > > > I guess we could also be busy-looping waiting for the event, but it
 > > > would not be nice to other guests domains.
 > > 
 > > if there's a way to poll events (i couldn't find any),
 > > i think it's better to use it because ddb needs to do busy-loop anyway.
 > 
 > Not here, xenconscn_getc() calls HYPERVISOR_yield() when it waits for
 > input, so it won't consume CPU. But HYPERVISOR_yield() won't return unless
 > interrupts are enabled.
 
 "interrupts" in what sense?
 i thought HYPERVISOR_yield left the calling domain runnable
 so it would be scheduled sooner or later.
 
 YAMAMOTO Takashi