From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gianni Tedesco <gianni.tedesco@citrix.com>
Subject: Re: HVM SMP linux guest hangs in cpu_idle() with
	EFLAGS.IF = 1
Date: Wed, 21 Jul 2010 18:29:43 +0100
Message-ID: <1279733383.1723.2003.camel@qabil.uk.xensource.com>
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Another data-point I have on this but haven't mentioned here yet is that
the userspace (anaconda) processes are usually hanging in
tty_wait_until_sent() which is apparently why things are woken up by
receiving a keypress on the serial line.

At other times the hang occurs while userspace (hotplug, also anaconda)
is waiting in do_poll() on a kernel netlink socket. In that case a
keypress on serial line also wakes it (!!)

Gianni Tedesco