From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH v2 2/5] arm: implement
	vcpu_mark_events_pending
Date: Fri, 24 Feb 2012 10:53:02 +0000
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To: Ian Campbell <Ian.Campbell@citrix.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, "Tim Deegan (3P)" <Tim.Deegan@citrix.com>, Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
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On 24/02/12 10:33, Ian Campbell wrote:
> On Thu, 2012-02-23 at 18:21 +0000, Stefano Stabellini wrote:
>> Implement vcpu_mark_events_pending using the vgic to inject INT 63, that
>> we reserve for Xen usage.
> 
> Does this require a trap when the guest acks or EOIs this interrupt?
> What about maintenance interrupts arising from injecting this?
> 
> Might we want to instead inject this interrupt as an SGI, so that it
> appears as a per-VCPU interrupt?

I don't think it's possible to register a SGI handler in Linux
currently.  The mapping of IRQ numbers to GIC interrupts skips over the
SGIs.  This would be easy to fix I think.

David