From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH 0/6] MSI-INTx interrupt translation for HVM
Date: Mon, 02 Mar 2009 09:40:40 +0000
Message-ID: <C5D15A18.3DCC%keir.fraser@eu.citrix.com>
References: <20090302092440.GA22064@ub-qhe2>
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To: Qing He <qing.he@intel.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Shohei Fujiwara <fujiwara-sxa@necst.nec.co.jp>
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On 02/03/2009 09:24, "Qing He" <qing.he@intel.com> wrote:

>> Ah, well the passthrough-specific logic is not something I'm so familiar
>> with! That above code indeed doesn't look correct. :-)
> 
> I recently learned that some device may keep issuing MSI until it is
> explicitly
> cleared by software. In that case it just behaves like level-triggered
> interrupt, and doing something like the code above will cause interrupt storm.
> This is reflected in cs. 19065.
> 
> Do you mean this issue?

That would be the expected result of early EOI, yes. But Shohei was walking
about losing interrupts. I don't know how we would do that.

 -- Keir