From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [VTD][patch 0/5] HVM device assignment using vt-d
Date: Thu, 31 May 2007 16:14:33 +0100
Message-ID: <C284A4E9.FC99%keir@xensource.com>
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To: "Tian, Kevin" <kevin.tian@intel.com>, Keir Fraser <keir@xensource.com>, Guy Zana <guy@neocleus.com>, "Kay, Allen M" <allen.m.kay@intel.com>, xen-devel@lists.xensource.com
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On 31/5/07 16:10, "Tian, Kevin" <kevin.tian@intel.com> wrote:

> Sure. :-) But I'm still thinking the effect to use virtual EOI as de-assertion
> signal, which doesn't require to change polarity in the line frequently. We
> can just add a flag per gsi to indicate whether a physical irq is injected
> on this line. When intercepting HVM EOI, invoke deassert and also jump
> to ->end() if flag is on. Does it work basically?

I didn't realise you were suggesting another mechanism. It's not clear to me
how it works from the very brief description you give above. Could you
provide an example or two for how your method would work (e.g., one which
avoids switching polarity, and another where you do end up switching
polarity)?

 -- Keir