From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: clear_IO_APIC() et al Date: Tue, 16 Aug 2011 09:25:20 +0100 Message-ID: References: <4E4A3C6C020000780005166E@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4E4A3C6C020000780005166E@nat28.tlf.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jan Beulich , alex.williamson@hp.com Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On 16/08/2011 08:46, "Jan Beulich" wrote: > In c/s 20650:b543acc1aaad you made clear_IO_APIC() call both > clear_IO_APIC_pin() and clear_IO_APIC_raw(), and I don't really > follow why the former would be necessary here - the only code > paths we care about are boot and shutdown/crash, and hence > all we want is clearing the actual IO-APIC RTEs (without regard > to interrupt re-mapping). > > Furthermore, even clear_IO_APIC_pin() is only called during early > boot, so it would seem to me that we should only need the "raw" > variant. > > The context of the question is the need to add some extra code > here to clear the remoteIRR bit if still set (e.g. during a crash), as > that bit remaining set can otherwise lead to later confusion (during > crash handling in the secondary kernel, and when booted through > kexec in Xen itself). I think Alex is @ Red Hat now, so unlikely to be of help here. You can feel free to propose whatever fixups and cleanups you like on that function. -- Keir > Jan >