From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: Re: [PATCH] x86: fix the potential of encountering
	panic "IO-APIC + timer doesn't work! ..."
Date: Fri, 12 Dec 2008 10:24:41 +0100
Message-ID: <20081212092441.GJ25106@elte.hu>
References: <20081212091329.GG25106@elte.hu>
	<C567DE15.20269%keir.fraser@eu.citrix.com>
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* Keir Fraser <keir.fraser@eu.citrix.com> wrote:

> On 12/12/2008 09:13, "Ingo Molnar" <mingo@elte.hu> wrote:
> 
> >>> From all I can tell, the below reproduced full description of the
> >> original Linux patch applies to Xen, too - at least in the watchdog
> >> enabled case IRQs can be enabled when entering setup_IO_APIC(). My
> >> attention to this change really got caught just by the fact that it got
> >> added to our (2.6.16-based) SLE10 kernel pretty recently.
> > 
> > note that we had to revert that eventually. The real solution is an 
> > array of fixes from Maciej spread out over many months.
> 
> Does it do more harm than good on some systems, or is it simply not a 
> comprehensive fix?

more harm than good - fixes some, breaks others. Have a look at the 
latest upstream io_apic.c, that has it all settled down reasonably well.

	Ingo